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I    II     II     II  III    (III  |l 

HX00060801 


RECAP 


SMITHSONIAN  CONTRIBUTIONS  TO  KNOWLEDGE. 


lf3o&ghin6  3Fun&. 


THE 


CoMPOSriTOX    OF    EXPIRED    AlR 


AND    ITS 


EFFECTS   UPON   ANIMAL   LIFE. 


J.  S.  BILLINGS.  M.D..  S.  WEIR  MITCHELL,  M.D. 
AND    D.   H.  BERGEY.  M.D. 


city  op  washington 
publi.>;hed  by  the  Smithsonian  in-^titution. 

1895. 


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Digitized  by  the  Internet  Archive 

in  2010  with  funding  from 
Columbia  University  Libraries 


http://www.archive.org/details/compositionofexpOObill 


SMITHSONIAN  CONTRIBUTIONS  TO  KNOWLEDGE. 
989  


ir^obtjlnns  Jfunb. 


THE 

Composition  of  expired  Air 

AND    ITS 
EFFECTS   UPON  ANIMAL   LIFE. 


J.  S.  BILLINGS,  M.D.,  S.  WEIR  MITCHELL,  M.D. 
AND    D.  H.  BERGEY,  M.D. 


CITY   OP   WASHINGTON  : 
PUBLISHED  BY  THE  SMITHSONIAN  INSTITUTION. 

1895. 


"■\ 


14^ 


COMMISSION     TO     WHOM     THIS     MEMOIR 
HAS    BEEN     REFERRED. 

HORATIO  C.  WOOD. 
WILLIAM   HF:NRY  WELCH. 
CHARLES  -SEDGWICK   MINOT. 


ADVERTISEMENT. 


The  preseut  iiieinoir  is  the  result  of  :i  series  uf  iuvestigations  made 
by  Doctors  J.  S.  Billings  and  S.  Weir  Mitchell,  assisted  by  Doctor  D.  II. 
Bergey,  undrr  a  Lcrant  from  the  Ilodgkins  Fund  of  the  Smithsonian 
Institution,  for  the  purpose  of  determining  the  nature  of  the  peculiar 
substances  of  organic  origin  contained  in  the  air  expired  l)y  human  beings, 
with  special  reference  to  the  practical  application  of  the  results  obtained 
to  problems  of  ventilation  for  inhabited  rooms. 

In  accordance  with  the  rule  adojtted  l)y  the  Smithsonian  Institution 
the  woik  has  been  submitted  to  a  committee,  in  the  present  instance  con- 
sisting of  Doctor  H.  C.  Wood,  Professor  ^^'illialn  II.  Welch,  and  Professor 
Charles  S.  Minot,  and  having  been  recommended  by  them  for  pul)lication, 
it  is  lierewitli  presented  in  the  series  of  Contrilnitions  to  Knowledge. 

S.  P.  LANGLEY, 

SECRETARY. 

Washington,  November,  1895. 


Ill 


The  Composition  of  Expired  Air,  and  its  Effects   upon 

Animal  Life. 


REPORT  ON  THE  RESULTS  OF    AN  INVESTIGATION  MADE    FOR  THE  SMITHSONIAN    INSTI- 
TUTION  UNDER  THE   PROVISIONS  OF  THE  HODGKINS  FUND. 

By  J.  S.  Billings,  M.D.,  S.  Weir  Mitchell,  M.D.,  and  D.  H.  Bergey,  M.D. 


In  May,  IS!);?,  a  grant  was  made  from  the  Hodgkins  Fund  to  Drs.  John  S. 
Billings  and  S.  Weir  Mitchell, "for  the  purpose  of  conducting  an  investigation  into 
the  natui'e  of  the  peculiar  substances  of  organic  origin  contained  in  the  air  expired 
by  human  beings,  with  special  reference  to  the  practical  application  of  the  results 
obtained  to  problems  of  ventilation  for  inhabited  rooms." 

For  a  number  of  3'ears  prior  to  1888  the  prevailing  view  among  physicians  and 
sanitarians  had  been  that  the  discomfort  and  dangers  to  health  and  life  which  had 
been  known  to  exist,  sometimes  at  least,  in  niiventilated  i-ooins  occupied  by  a  num- 
ber of  human  beings,  were  largely  or  entirely  due  to  peculiai-  organic  matters  con- 
tained in  the  air  expired  by  these  persons,  and  that  the  inci'ease  in  carbonic  acid 
due  to  respiration  had  but  little  effect  in  jiroducing  these  results,  its  chief  import- 
ance being  that  it  furnished  a  convenient  means  of  determining  the  amount  of 
vitiation  of  the  air.  Recently,  however,  sevei'al  experimenters  have  concluded  that 
the  organic  matters  in  the  exhaled  breath  are  not  harmful,  at  all  events  to  animals, 
and  tlie  main  object  of  the  pi'oposed  investigation  was  to  determine  the  correctness 
of  these  conclusions.  Foi-  this  purpose  a  scheme  of  experimentation  was  prepared 
by  Di's.  Billings  and  Mitchell,  \vhich  scheme  has  been  carried  out  in  the  Laboratory 
of  Hygiene  of  the  Univei'sity  of  Pennsylvania,  by  Dr.  D.  H.  Bergey,  assisted  at 
times  in  the  chemical  work  by  Di'.  Hill  S.  Warwick,  and  in  some  of  the  pathological 
investigations  by  Dr.  Ingersoll  Olmsted,  and  under  the  general  supervision  of  Dr. 
A.  C.  Abbott,  First  Assistant  in  the  Laboratory,  to  whom  thanks  are  due  for  many 
valuable  suggestions  duiing  the  progress  of  the  work.     From  time  to  time  Dr. 


■2  THE  COMPOSITION  OF  EXPIRED  AIR, 

Bei'gey's  notes  on  tlie  results  of  liis  experiincnits  linve  been  submitted  to  Drs.  Bill- 
ings and  Mitchell,  who  have  suggested  niodificatious  or  new  experiments  as  the 
work  progressed.  Tiiis  re[)ort  is  based  on  these  notes,  and  accom[ianying  tables  and 
ciiarts,  given  in  tlie  Appendix. 

The  effects  produced  on  animals  and  men  by  an  atmos[)liere  contaminated  with 
tlieir  exhalations,  and  with  pai'ticulate  matters  derived  from  their  bodies  or  their 
immediate  surrouiulings,  may  be  divided  into  acute  and  chrt)nic.  The  acute  effect 
may  be  death  in  a  few  minutes  or  hcnirs,  as  shown  l)y  the  results  oliserved  in  the 
Black  Hole  of  Calcutta,  in  the  steamei'  Londonderry,  and  in  many  of  the  experi- 
ments referred  to  in  this  report,  oi'  it  may  be  simply  great  discomfoi't,  especially  in 
those  unaccustomed  to  such  conditions. 

The  chronic  effects  include  the  favoring  of  the  action  of  certain  specific  causes 
of  disease  commonly  known  as  contagious,  if  these  are  present,  and  perhaps  also  a 
general  lowei'ing  of  vitality. 

The  statistical  evidence  collected  by  the  English  Barrack  and  Hospital  Com- 
mission (1)  *  as  to  tlie  effects  of  insufficient  ventilation  upon  the  health  of  soldiei's 
in  barracks,  published  in  18(U,  showed  that  men  who  live  for  a  considerable  portion 
of  their  time  in  badly  ventilated  rooms  have  higher  sickness  and  death-rates  than 
have  tliose  who  occujiy  well  ventilated  rooms, other  conditions  being  the  same;  and 
this  has  also  been  found  to  be  true  with  regard  to  monkeys  and  other  animals.  It 
is  evident,  however,  that  in  a  room  occupied  by  animals  or  men  there  are  many 
sources  of  impurity  besides  the  exhaled  breath,  and  it  is  still  a  question  whether  the 
expii'ed  air  contains  substances  injurious  to  life,  excluding  carbonic  acid. 

The  widely  divergent  result^  obtained  and  conclusions  reached  by  diffei'ent 
investigators  during  the  last  ten  years  as  to  \vhether  the  exlialed  breath  of  men  and 
animals  contains  a  peculiar  volatile  organic  poison,  have  made  it  desiraljJe  to  repeat 
and  var}'  such  experiments  in  oi'der,  if  possible,  to  settle  this  important  point.  The 
chemical  analyses  of  the  air  of  overcrowded  rooms,  and  the  experiments  upon 
animals  with  various  proportions  of  carbonic  acid,  made  by  many  investigators, 
indicate  that  the  evil  effects  observed  are  probably  not  due  to  the  comparatively 
small  propoiiions  of  carbonic  acid  usually  found  under  such  circumstances. 

It  was  shown  by  Leblanc  (2),  in  1842-43,  that  an  animal  can  breathe  an 
atmosphere  containing  as  much  as  30  per  cent,  of  carbonic  acid  for  three-quarters  of 
an  hour,  provided  that  the  percentage  of  oxygen  was  70,  and  then  quickly  recover 
from  the  depression  induced  by  this  mixture  after  removal  to  the  normal  atmos- 
phere.    He  also  demonstrated  that  under  the  conditions  in  which  the  quantity  of 

*  The  numbers  in  parentheses  refer  to  the  bibliographical  list  appended  to  this  report. 


^  AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  3 

carbonic  acid   rises  perceptibly  in  theatres,  etc.,  the  reduction  of  oxygen  is  quite 
insignificant,  and  tliat  the  pi'oportion  larcly  falls  below  20  per  cent. 

Regnault  and  Reiset,  (3),  iu  1849,  also  found  that  when  sufficient  oxygen  is 
supplied  to  an  atmosphere  quite  rich  in  cai'bonic  acid,  an  animal  can  still  live  in  it. 
FrieiUiiniler  and  llerter  (4)  found  that  the  breathing  of  an  atmosphere  containing 
20  per  cent,  of  carbonic  acid  for  an  hour  produced  no  symptoms  of  depression,  but 
caused  stinuilation  of  the  respiratory  centres  and  an  increased  activity  of  the 
heart. 

Claude  Bernard  (5),  in  1857,  experimented  with  animals  confined  in  atmos- 
pheric air  and  in  mixtures  both  richer  and  poorer  in  oxygen  than  atmospheric  air. 
A  small  bird  placed  in  a  bell  glass  of  a  little  moie  than  two  litres'  capacity,  containing 
a  mixtui'e  of  13  per  cent,  carbonic  acid,  39  per  cent,  oxygen,  and  48  per  cent,  of 
nitrogen,  died  in  two  and  one-half  hours.  He  demonstrated  tliat  carl)onic  acid  is 
not  poisonous  when  injecteil  under  the  skin  of  animals — as  much  as  one  litre 
injected  under  the  skin  of  a  i-abbit  producing  no  ill  effects.  No  ill  effects  followed 
the  injection  of  the  gas  into  the  jugular  vein  and  into  the  carotid  arterj-.  An 
atmosphere  of  eipial  parts  of  oxygen  and  nitrogen  had  no  effect  upon  an  animal 
confined  in  it,  while  an  atmosphere  composed  of  equal  parts  of  carbonic  acid  and 
of  oxygen  produced  inunediate  death  in  the  animal  placed  in  it.  lie  explains  the 
poisonous  effects  of  carbonic-  acid  when  respired  to  be  due  to  the  fact  that  it 
deprives  the  animal  of  oxygen.  Similar  results  were  reported  by  Valentin  ((>) 
and  by  Paul  Bert  (7). 

Richardson,  in  1860-01,  (8),  found  that  a  temperature  much  higher  or  lower 
than  20°  C.  had  the  effect  of  shortening  very  considerably  the  lives  of  animals  con- 
fined in  an  unventilated  jai',  and  that  these  effects  were  more  marked  when  the 
animals  were  confined  in  an  atmosphere  richer  iu  oxygen  than  air,  in  which  case 
he  found  that  by  passing  electric  sparks  from  a  fiictional  machine  through  the 
fatal  air  (having  previously  de[)i'ived  it  of  its  carbonic  acid)  it  was  again  made 
capable  of  supporting  life,  from  which  he  concluded  that  the  oxygen  is  "  devital- 
ized "  during  i-espiration,  and  that  the  electric  spark  has  the  faculty  of  revital- 
izing it. 

Von  Pettenkofei',  in  1860-63,  (9),  showed  that  the  symptoms  observed  in 
crowded  ill-ventilated  places  were  not  [)roduced  by  the  excess  of  carbonic  acid,  noi- 
by  a  decrease  in  the  proportion  of  oxygen  in  the  air;  neither  of  these  being  suffi- 
cient in  our  dwellings,  theatres,  etc.,  to  produce  toxic  effects.  He  did  not  believe 
that  the  impui'e  air  of  dwellings  was  directly  capable  of  originating  specific  dis- 
eases, or  that  it  was  really  a  poison  in  the  ordinary  sense  of  tlie  term,  but  that  it 
diminished  the  capability  of  withstanding  the  influence  of  disease-producing  agen- 


4  THE  COMPOSITION  OF  EXPIRED  AIR, 

cies  on  the  part  of  those  continually  breathing  snch  aii-,  and  laid  down  the  rule, 
which  has  been  accepted  and  taught  by  sanitaiians  for  thii'ty-five  years,  that  the 
proportion  of  carbonic  acid  in  the  atmosphei'e  of  inhabited  places  affords  a  safe 
indication  as  to  the  amount  of  the  other  impurities  resulting  from  respiration  and 
other  exhalations  from  the  bodies  of  the  occupants. 

Hammond,  in  1863,  (10),  reported  experiments  in  which  he  sought  to  remove 
the  carbonic  acid  and  moisture,  and  to  supply  fresh  air  as  fast  as  it  is  needed  to 
take  the  place  of  the  carbonic  acid  removed,  thus  leaving  the  "  organic  matter"  to 
accumulate  in  the  vessel.  For  this  purpose  he  confined  a  mouse  in  a  large  jar,  in 
which  were  several  sponges  saturated  with  baryta-water,  by  which  the  carbonic 
acid  was  removed  as  fast  as  formed.  Fresh  air  was  supplied  as  fast  as  required  by 
means  of  a  tube  communicating  with  the  bell  jar  and  closed  by  water  in  the  bend 
of  the  tube,  which  acted  as  a  valve.  As  the  air  in  the  bell  glass  was  rarefied  by 
respiration  and  absorption  of  the  carbonic  acid,  fresh  air  flowed  in  from  without, 
while  the  arrangement  of  the  tube  prevented  the  air  of  the  bell  glass  from  passing 
out.  The  watery  vapor  exhaled  by  the  animal  was  absorbed  by  two  or  three 
small  pieces  of  chloride  of  calcium.  The  mouse  died  in  forty  minutes.  The 
observation  was  repeated  many  times,  and  death  ensued  invariably  in  less 
than  an  hour.  On  causing  the  vitiated  air  to  pass  through  a  solution  of 
permanganate  of  potash  the  presence  of  organic  matters  in  large  quantity  was 
demonstrated. 

Ransonie,  in  1870,  (11),  reported  a  series  of  very  interesting  investigations 
upon  "  Oiganic  Matter  of  Human  Bi'eath  in  Health  and  Disease."  By  condensing 
the  aqueous  vapor  of  the  human  breath  and  analyzing  it  by  the  Wanklyu  and 
Chapman  method,  he  found  that  "in  ordinary  respiration  about  0.2  g.  of  organic 
matter  is  given  off  from  a  healthy  man's  lungs  in  24  hours,"  while  in  the  air 
expii'ed  by  persons  affected  witb  certain  diseases,  he  found  great  variations  in  the 
amount  of  organic  matter,  the  amount  being  greatest  in  a  case  of  phthisis  compli- 
cated with  Bright's  disease. 

Smith  (12)  employed  a  lead  chamber  in  his  investigations  upon  the  question 
whether  human  lungs  give  off  any  poisonous  agent  other  than  carbonic  acid.  He 
found  the  pulse  to  fall  from  73  to  57  beats  per  minute,  and  the  number  of  respirations 
to  rise  from  15.5  to  24,  as  the  carbonic  acid  in  the  atmosphere  increased  fiom  .04 
to  1.73  per  cent,  during  four  hours.  When  the  proportion  of  carbonic  acid  I'ose  to 
3  per  cent,  there  appeared  great  w"eakness  of  the  circulation  with  slowing  of  the 
heart's  action,  and  great  difhculty  in  respiration.  He  believed  that  these  results 
should  be  attributed  to  other  conditions  rather  than  to  the  excess  of  carbonic  acid, 
because  lie  found  later  that  it  was  only  when  lamps  became  dim  in  an  atmosphere 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  5 

— indicating  a  proportiou  of  about  10  per  cent,  of  carbonic  acid  present — that  tlie 
respii'ation  became  dillicult. 

Seegen  and  Nowak,  in  1879,  (13),  believed  thej'  had  demonstrated  the  presence 
of  poisonous  orpiuic  niattei'  in  the  expired  lireath,  l)ut  the  (piautity  fouud  was  so 
small  that  they  failed  to  determine  its  exact  nature  and  properties. 

Hermans,  in  1883,  (l-l),  was  unable  to  detect  any  organic  matter  in  the  atmos- 
phere of  a  tin  cage  in  \\liich  several  persons  had  been  confined  for  a  number  of 
luuirs,  and  found  that  an  atmosphere  containing  from  2  to  4  per  cent,  of  carbonic 
acid  and  1;")  per  cent,  of  oxygen  was  not  toxic. 

Browu-Scquard  and  d'Arsonval,  in  1887,(15),  reported  that  the  air  expired  by 
men  and  dogs  in  a  state  of  health  has  the  power  of  producing  toxic  [)henoniena; 
citing  three  series  of  experiments  on  rabbits  where  such  phenomena  were  observed. 
In  the  fii'st  series  they  injected  into  the  vascular  system  of  a  rabbit  4  to  6  c.  c.  of 
fluid  obtained  by  injecting  from  15  to  25  c.  c.  of  pure  filtered  water  into  the 
trachea  of  a  dog.  In  a  second  series,  fi-om  6  to  7  c.  c.  of  a  li(pii(l  obtained  by  con- 
densing the  moisture  in  the  exhaled  breath  of  a  man,  were  injected  into  the  aorta, 
or  into  a  vein,  of  a  rabl)it.  In  the  third  series  fi'om  4  to  6  c.  c.  of  a  licpiid,  obtained 
by  condensing  the  moisture  in  the  exhaled  breath  of  a  tracheotomized  dog,  were 
used.  The  condensed  liquid  thus  obtained  was  filtered  and  then  injected  either 
into  the  jugular  vein  or  the  carotid  arteiy. 

The  symptoms  observed  were  dilatation  of  the  pupils  and  increase  of  the  heart- 
beat to  240,  280,  or  even  320  per  minute,  lasting  for  several  days  or  even  weeks. 
The  temperature  remained  noi-mal ;  the  i'es])ii-atory  movements  were  generally 
slowed  ;  and  usually  there  was  observed  paralysis  of  the  j^ostei'ior  members 
Choleraic  diarrhoea  was  invariably  present.  Death  usually  took  place  in  a  few 
days,  or  at  the  farthest  in  four  or  five  weeks.  As  a  rule,  it  appeared  that  larger 
doses  caused  laboi-ed  respiration,  violent  retching,  and  conti-acted  pupils.  A  rapid 
lowering  of  temperature,  0.5  °  to  5.°  C,  was  sometimes  observed.  The  appearances 
that  presented  p'jf^t  mortc-in  were  much  like  those  observed  in  cardiac  syncope. 

They  believed  they  had  discovered  a  volatile  organic  poison  in  the  exhaled 
breath  and  the  moisture  condensed  fi'om  it.  This  poison  they  believed  to  be  of 
the  nature  of   an  oi'ganic  alkaloid,  or  a  2)toniaine  not  unlike  Brieger's  ptomaine 

(16). 

In  further  reports,  in  1888,  (17),  they  state  that  none  of  eleven  rabbits  in 
which  the  condensed  pulmonaiy  vapor  had  been  injected  into  the  vascular  system 
in  doses  of  12  to  30  c.  c.  survived,  but  of  eight  rabbits  receiving  an  injection  of 
from  4  to  8  c.  c,  three  were  living  after  the  lapse  of  from  four  to  five  weeks,  but 
were  then  weak.     When  the  fluid  was  injected  under  the  skin  of  the  thorax  and 


6  THE  COMPOSITION  OF  EXPIRED  AIR, 

ill  the  axilla,  five  out  of  seven  i'al)l)its  died  ia])i(lly.  'J'lie  results  were  iiiucli  tlie 
same  as  when  it  was  injected  into  tiie  blood.  The  (juantity  of  the  condensed  liquid 
injected  iu  these  seven  was  :  20  e.  c.  in  one  case,  25  c.  c.  in  three  cases,  ?>]  c.  c.  in 
one  case,  40  c.  c.  in  one  case,  and  44  c.  c.  in  another  case.  After  death,  consider- 
able congestion  of  the  viscera  was  noted,  especially  of  the  lungs.  No  appearance 
of  embolism  was  noted.  The  brains  and  its  membranes  were  congested,  but  with- 
out visible  lesion.  The  condensed  liquid  turns  concentrated  sulphuric  acid  yellow. 
The  poison  is  reduced  by  anunoniacal  nitrate  of  silver  solution  as  well  as  by  chloride 
of  gold.  After  boiling  in  a  close  vessel  it  is  still  toxic,  showing  that  the  poison  is 
not  a  inicro-orgauisra.  Tiie  boiled  lung  licpiid  poisons  with  more  rapidity  than  that 
which  has  not  been  sterilized,  and  may  kill  a  pigeon  and  a  guinea-pig  as  well  as  a 
rabbit;  it  may  kill  by  being  injected  into  the  rectum  or  into  the  stomach;  a 
guinea-pig  two  months  old  was  killed  within  twelve  hours  by  an  injection  of  3  c.  c. 
into  the  peritoneal  cavity.  If  injected  into  the  lungs  this  li(|uid  jiroduces  rapid 
congestion  followed  by  true  inflammation  and  red  hepatization. 

In  an  expei'iment  with  two  dogs  it  was  arranged  that  one  breathed  ordinary 
air  and  the  second  inhaled  air  which  came  from  the  lungs  of  the  other.  The  dogs 
were  of  the  same  weight,  15  kilograms.  The  experiment  continue!,!  for  six  houi'S 
and  forty  minutes.  No  appreciable  or  immediate  consecutive  accidents  wei'e 
[)roduced. 

In  a  second  experiment  the  pulmonary  liquid  was  collected  from  dogs  through 
a  tracheotomy  tube  to  exclude  impurities  furnished  by  the  mouth.  The  air  inhaled 
was  first  washed  to  remove  dust.  The  moisture  in  the  air  expired  was  condensed, 
and  the  liquid  collected  in  a  flask  surrounded  by  ice.  At  the  moment  of  injection 
this  liquid  was  filtered,  and  was  then  injected  at  the  temperature  of  the  laboratory, 
about  12°  C.  If  the  animal  was  kept  immovable  from  12  to  IG  hours,  inflammation 
of  the  air  passages  was  produced.  The  li(]uid  of  the  first  hours  came  from  a 
thoroughly  sound  lung,  and  in  the  later  hours  from  a  diseased  lung.  The  two 
wei'e  collected  sepai'ately  and  tried  separately.  For  one  kilogram  of  the  animal, 
for  each  hour,  the  mean  quantity  of  fluid  obtained  was  0.38  grammes,  varying 
from  0.28  to  0,48  grammes.  It  was  greater  in  the  beginning  and  lessened  the  longer 
the  animal  was  kept  in  a  fixed  position.  It  was  injected  into  the  marginal  vein  of 
the  ear  of  a  rabbit  1)y  means  of  a  syringe,  75  c.  c.  being  injected.  When  the  injec- 
tion did  not  exceed  40  to  50  c.  c.  the  time  occupied  by  the  injection  was  fi-om  G  to 
15  minutes.  Experiments  made  by  injections  upon  the  dog  were  negative  with- 
out exception.  Experiments  made  upon  the  rabbit  produced  lesions,  but  the 
relation  between  these  and  the  injections  was  uncertain. 

Dastre  and  Loye,  in   1888,  (18),  reported   that  they  had  exposed  one  dog  to 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  7 

the  expiretl    breath   of  auother  for  six    lioiirs   without   noting  any  effects.     They 
inoculated  animals  with  the  condeused  moisture  of  respiration,  as  follows  : 

5  rabbits,  each  ;^^  to  75  c.  c.  of  the  fiiiid.     Results  negative. 

((  H  ii  ii  il  ti  (( 

2  guinea-pigs,  5  7 

da  u     _         t4  ((  it  u  It 

ogs,  30        53 

2  frogs,  "        2    "     3     "         "  

2  rabbits,  "     50    "190     "         "  "  Died. 

A  young  dog,  30     "     of  water. 

They  found  tiiat  .'30  to  70  c.  c.  of  the  condensed  fluid  of  respiration  (20  to  35 
CO.  per  kilo.)  could  be  injected  into  the  veins  of  the  ear  of  a  dog  without  producing 
any  of  the  symptoms  reported  liy  Browu-Secpiard  and  d'Arsouval.  They  observed 
one  death  during  the  injection  of  190  c.  c.  ((50  c.  c.  per  kilo.),  yet  by  control  experi- 
ments with  water  tiicy  obtained  a  more  remarkable  result — a  rapid  death  from  the 
injection  of  30  c.  c.  of  distilled  water  (25  c.  c.  per  kilo.). 

Ru.sso-Gililierti  and  Alessi,  in  1888,  (19),  reported  experiments  confirming  the 
results  obtained  by  Dastre  and  Loye. 

Wi'irtz,  in  1888,  (20),  attempted  to  obtain  the  "  ptomaine  "  of  BrownSequai'd 
and  d'Arsonval  from  the  Huid  condensed  from  expired  air.  By  expiring  through  a 
1  per  cent,  solution  of  oxalic  acid  he  obtained,  besides  ammonia,  a  volatile  orgaiuc 
base  which  was  [irecipitated  by  Bouchardet's  reagent  and  by  potassio-mercuric 
iodide.  With  platiiiic  chloride  it  formed  a  double  salt,  crystallizing  in  short  needles, 
and  a  soluble  salt  with  auric  chloride.  When  heated  to  100°  C.  it  gave  off  a 
pecidiar  odor.  This  basic  substance,  he  thought,  might  be  regarded  as  a  leuco- 
maine. 

Brown-Seqnard  and  d'Arsonval,  in  1889,  (21),  reported  a  new  form  of  experi- 
ment by  means  of  which  they  obtained  additional  evidence  in  su]i}>ort  of  their  for- 
mer statements.  The  new  form  of  experiment  consisted  in  confining  animals 
(rabbits)  in  a  series  of  metallic  cages  connected  by  means  of  i-ubber  tubing,  through 
which  a  constant -current  of  air  is  aspirated.  The  animal  in  the  last  cage  of  the 
series  receives  air  tiiat  has  tiaversed  the  entii'e  series  of  cages,  and  is  loaded  with 
the  impurities  from  the  lungs  of  the  animals  in  the  other  cages.  This  animal  suc- 
cumbs, after  a  time,  to  the  atmospheric  conditions  present.  After  another  interval 
of  some  hours,  the  animal  in  the  next  to  the  last  cage  also  dies;  the  first  and  second 
animals  usually  remaining  alive.  They  could  not  attribute  the  death  of  these 
animals  to  excess  of  carbonic  acid  in  the  atmosphere  of  the  cages,  because  they 
rarely  found  more  than  3  pei'  cent,  of  this  gas  in  the  last  jar  with  small  animals,  or 
6  per  cent,  with  larger  animals.  On  placing  absorption  tubes  containing  concen- 
trated Hg  SO^  between  the  last  two  cages,  the  animal  in  the  hist  cage  remained 


8  THE  COMPOSITION  OF  EXPIRED  AIR, 

alive,  while  that  in  the  cage  before  it  was  the  first  to  die.  They  coucluded  fi-om 
these  facts,  that  the  death  of  the  animals  was  produced  by  a  volatile  poison,  which 
poison  is  absorbed  by  the  IlgSO^,  which  thus  saves  the  life  of  the  animal  in  the  last 
cage. 

They  stated  (22)  that  any  alkali  used  to  absorb  carlionic  acid  from  expired  air 
would  also  change  the  organic  jx^if'ou,  and  [)i-oposed  an  ajiparatus  by  means  of 
\vliicli  the  oi-ganic  poison  should  be  supplied  to  the  fresh  air  entering  the  jars  by 
volatilizing  it  from  fluid  condensed  from  the  expired  air. 

Von  Hofmauu-Wellenhof,  in  1888,  (23),  found  that  when  he  injected  large  quan- 
tities of  the  condensed  fluid  of  respiration  at  12  °  C,  instead  of  at  37  °  C. — intravenous 
injection, — a  resemblance  of  the  results  obtained  by  Brown-Sequard  and  d'Arsonval 
was  produced.  Under  such  cii'cumstances  he  observed  muscle  %veakness,  slowing 
of  respiration,  fall  of  temperature,  and  dilatation  of  the  pupils,  though  the  animals 
remained  alive.  He  injected  10  rabljits  with  6  to  30  c.  c.  of  the  fluid  warmed  to 
the  body  temperature,  all  the  I'esults  being  negative.  Tliree  other  animals  were  in- 
jected in  the  jugular  vein^one  receiving  28  c.  c.  of  the  fluid,  another  25  c.  c. 
of  distilled  water,  and  a  third  50  c.  c.  of  distilled  water.  There  was  no 
difference  in  the  symptoms  noted  in  the  animals.  He  noticed  synqitoras  of  depres- 
sion only  after  injecting  50  c.  c,  or  more,  of  the  fluid.  In  a  series  of  17  experiments 
with  inoculations  of  from  30  to  50  c.  c.  each  of  the  fluid,  in  12  there  appeared 
hiemoglobinuria ;  6  of  these  died.  As  the  i-esult  of  his  experiments,  he  concluded 
that  the  existence  of  a  volatile  poison  in  the  expired  aii'  of  healtliy  human  beings 
has  not  been  demonstrated  by  his  experiments ;  this  being  a  direct  contradiction  of 
the  results  of  Bi'own-Sequard  and  d'Arsonval,  as  were  also  those  of  Dastre  and 
Loye. 

Uft'elmann,  in  1888,  (24),  found  that  there  was  a  perceptible  increase  in  organic 
matter  in  the  atmosphere  of  a  sleeping-room  occupied  by  several  persons  for  some 
hours,  increasing  in  amount  with  the  length  of  time  the  room  was  occupied. 

Lehmann  and  Jessen,  in  1890,  (25),  collected  15-20  c.  c.  of  condensed  fluid  per 
hour  from  the  breath  of  a  i)erson  exhaling  through  a  glass  spiral  laid  in  ice.  The  fluid 
was  always  clear  as  water,  odoi'less,  and  of  neutral  reaction.  Nessler's  reagent  showed 
the  presence  of  ammonia  constantly,  with  good  teeth  l)ut  little,  sometimes  merely 
a  trace,  with  bad  teeth,  more,  though  never  more  than  10  mg.  of  NH^Cl  in  one  litre. 
Traces  of  HCl  were  also  constantly  found.  A  small  sediment  remained  on  evapora- 
tion, ranging  from  39  to  86.4  mg.  per  litre  of  fluid.  This  they  believed  to  originate 
from  the  glass  vessel ;  being  probably  calcium  oxalate.  They  tested  its  reducing 
power  upon  solution  of  permanganate  of  potash,  making  two  control  determinations. 
The  first  determination  showed  3.6  mg.  of  O  for  the  oxidation  of  1  L. ;  the  second, 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  9 

4.2  iiig.  of  O.  They  were  unable  to  obtain  any  alkaloiil  reaetioir  in  the  condensed 
fluid,  or  in  its  distillates,  by  means  of  PtCl,,,  An  CIg,  KCdl,  KBil,  KI,  Roucliardet's 
reagent,  KgCrOg,  [)icric  acid,  metawolfraniic  acid,  or  j)liosphowolframic  acid. 
Oidy  siiblinuite  gave  at  times  an  opalescence  wlncli,  like  the  yellow  coloration  of 
the  Xessler  reagent,  pointed  to  traces  of  Nil,.  Neither  could  they  succeed,  accord- 
ing to  the  method  of  Wi'irtz,  in  obtaining  a  lime  or  o.xalic  acid-free  filtrate.  The 
ammoniacal  silver  solution,  according  to  Brown-Sequard  and  d'Arsonval's  method, 
failed  to  give  the  desired  reaction — remaining  clear.  They  confined  a  man,  (•lMtlie<l 
in  his  \vorkin<j  clothes,  in  a  zinc  cage  ft)r  about  one-half  an  hour,  then  allowed  a 
boy  and  girl  to  inhale  the  air  from  the  cage.  No  ill  effects,  exce2>t  increase  of 
respirations  to  30  and  40  per  minute,  were  noticeable.  They  had  complete  negative 
results  from  inoculations  of  condensed  fluid  into  animals. 

Lipari  and  Crisafulli,  in  1889-90,  (26),  reported  results  which  were  in  accoixl 
with  those  of  Dastre  and  Loye,  and  directly  opposed  to  those  of  Browu-Sc(piaid 
and  d'Arsonv;d.  They  could  find  no  organic  principle  possessing  toxic  properties 
in  the  expired  breath  of  healthy  ^icrsons. 

Mai'gouty,  in  1891,  (2V),  reported  the  residts  of  experiments  similar  to  those 
of  Ilannuond,  and  also  of  experiments  in  injecting  fluid  condensed  from  expired  air 
into  animals.  His  results  did  not  correspond  to  those  reported  by  Hammond,  and 
there  was  no  evidence  of  toxic  propei'ties  in  the  injected  fluids. 

Haldane  and  Smith,  in  1892,  (28),  published  an  account  of  expei'imeuts  in 
which  an  aii'-tight  chamber,  6  feet  2  inches  high,  2  feet  11  inches  wide,  and  3  feet 
11  inches  long,  was  employed.  Samples  of  air  for  analysis  were  drawn  off 
through  a  tube  placed  in  the  wall  of  the  chamber,  about  three  feet  from  the  floor. 
When  one  person  remained  in  this  chamber  until  the  vitiation  was  from  ten  to 
twenty  times  as  great  as  in  the  most  crowded  and  woi'st  ventilated  public  build- 
ings, there  was  no  perceptible  odor  or  sense  of  oppression.  Air  vitiated  to  such  an 
extent  as  to  completely  prevent  a  match  from  burning  had  uo  appreciable  effect 
upon  the  subject  of  the  exjierinient.  In  other  experiments  hyperncea  and  other 
phenomena  produced  were  apparently  due  to  the  increased  proportion  of  carbonic 
acid. 

With  rabbits  weighing  1800  grammes,  Laematuria  was  produced  when  the 
amount  of  boiled  distilled  water  injected  passed  beyond  100  c.  c,  and,  therefore, 
80  c.  c.  were  taken  as  the  maximum  dose. 

To  obtain  the  condensed  liquid  from  the  lungs,  a  man  expired  thi'ough  a  Lie- 
big  condenser,  in  the  jacket  of  which  was  flowing  a  stream  of  ice-cold  water.  Tlie 
condensation  liquid  was  collected  in  a  flask,  the  bulb  of  which  was  buried  in  ice ; 
and  when  the  required  amount  (80  c.  c.)  had  been  obtained,  it  was  at  once  injected 


10  THE  COMPOSITION  OF  EXPIRED  AIR, 

iiiti)  Ihe  suhcutafieoiis  tissue  of  the  hack.  Six  rabl)its  were  tlms  injected,  eacli 
with  80  c.  c.  of  the  fluid,  witli  no  evident  distiirhance  of  liealtii  in  any  of  tlieui; 
80  c.  c.  to  a  ral)l)it  coiTesjxmds  to  a  dose  of  al)out  .'5  litres  to  a  man.  Tiiey  also 
re[)eated  the  e.\|teriiuents  of  l>rown-Se(juai'd  and  d'Arsonval  in  supplying  to  the 
animals  air  cliarged  with  oi'ganic  matter  drawn  directly  from  the  lungs  of  other 
animals.  Two  large  rabbits  were  placed  iu  an  air-tight  chamber  and  a  curi'ent  of 
air  diawn  through  this  was  supplied  to  two  yoUng  rabbits  under  observation  ;  no 
efi'ect  was  produced. 

Mei-kel,  iu  1892,  (29),  reported  an  experiment  iu  which  four  air-tight  glass 
vessels,  of  U  litres  capacity,  were  couuected  by  means  of  glass  tubes;  a  mouse 
being  placed  in  each  vessel.  Between  the  third  and  fourth  vessels  a  Geissler 
absorption  tube,  containing  sulphuric  acid,  was  interposed.  Air  was  now  drawn 
slowly  through  the  vessels  by  means  of  an  aspiratoi',  so  that  the  second  mouse 
breathed  the  air  from  the  first,  the  third  from  that  of  the  second,  etc.  The  result 
was,  just  as  in  the  experiment  of  Brovvu-Sequard  and  d'Arsonval,  that  the  mouse 
iu  the  third  vessel  died  iirst,  after  16-20  hours,  while  that  in  the  fourth  vessel 
remained  alive. 

The  conclusion  is  drawn  that,  as  the  fourth  mouse  remained  alive,  the  death 
of  the  third  cannot  have  been  due  to  excess  of  carbonic  acid,  or  deficiency  of 
oxygen  in  the  air,  but  must  have  been  caused  by  the  presence  of  some  volatile 
substance  which  is  absorbed  or  destroyed  by  sulphuric  acid. 

The  symptoms  presented  by  the  mice  before  death  were  at  fii'st  restlessness 
and  gradually  increasing  acceleration  of  respiration,  afterward  slowing  of  respira- 
tion, and  finally  spasmodic  deep  I'espirations,  becoming  constantly  less  frequent 
until  the  advent  of  death.  The  proportion  of  carbonic  acid  in  the  air  led  through 
the  glass  vessels  was  not  poisonous ;  it  amounted  iu  the  highest  case  to  1.5  per 
cent. 

Merkel  also  conducted  the  expired  breath  through  HCl  with  the  idea  of  com- 
bining the  organic  matter  with  it,  and  believed  he  was  successful,  but  the  quantities 
of  the  "salts"  produced  were  so  small  that  determination  of  their  chemical  nature 
was  impossible.  His  experiments  upon  animals  with  this  body,  obtained  from  its 
combination  by  neutralization  of  the  acid,  gave  negative  results. 

He  concludes  that  the  expired  breath  of  healthy  persons  contains  a  volatile 
poison  in  exti'emely  small  quantities ;  being  probably  a  base  which  is  poisonous  in 
its  gaseous  state,  but  loses  its  toxicity  after  combination  with  acids.  His  belief 
in  the  toxicity  of  the  organic  matter  contained  in  the  expired  breath  of  human 
beings  is  based  solely  ujion  the  results  he  obtained  iu  the  "  Brown-Sequard  and 
d'Arsonval"  experiment. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  1  1 

llaldane  and  Sinitli,  in  1893,(30),  repeated  the  "  Brown-Sequard  "  experiment, 
using  five  bottles,  each  of  a  capacity  of  1  to  H  litres,  connected  by  means  of  tubes. 
A  mouse  was  placed  in  vafii  l)ottlo  and  ventilation  established  through  the  whole 
system  by  means  of  a  filter  pump  ;  a  small  meter  being  placed  between  the  last 
bottle  and  the  pump.  Specimens  of  air  leaving  the  last  l)ottle  were  drawn  of?  at 
intervals  for  analysis.  Full-grown  mice  were  used.  Tiic  mice  in  the  last  two 
bottles  were  exposed  to  the  full  effect  of  the  vitiated  air  for  53  hours  without 
detriment. 

In  a  second  experiment  an  absorption  tube  containing  pumice-stone  saturated 
^vith  sulphuric  acid  was  placed  between  the  last  two  bottles.  This  experiment 
was  continued  for  thirty  hours  ;  no  serious  effects  were  observed.  The  amount  of 
ventilation  funiislicd  was  from  12  to  24  litres  pei'  hour.  The  mice  remained 
iiDrmal  after  having  been  in  the  bottle  three  days  and  the  percentage  of  carbonic 
acid  in  the  last  bottle  had  varied  from  2.4  to  5.2,  avei'aging  about  3. 

They  state  that  these  expei'iinents,  like  their  former  ones  on  rabbits  and  man, 
ai'e  distinctly  against  the  theoiy  that  a  volatile  poison,  other  than  carbonic  acid, 
exists  in  the  expired  air. 

Beu,  in  1893,  (31),  repoiied  the  results  of  experiments,  made  undci'  the  direc- 
tion (if  Uffelmann,  in  which  the  condensed  moisture  of  expired  aii-  was  collected 
by  the  methods  usually  employed,  taking  the  pi'ecaution  to  cleanse  his  apparatus 
with  solution  of  K^InO^  and  distilled  water,  and  likewise  stei'ilizing  the  ai)paratus 
befoi'e  it  was  brought  into  use.  The  saliva  is  collected  in  a  Woulff  bottle  attached 
before  the  condenser.  The  amount  of  air  expired,  measured  by  a  gas  metei",  was 
found  to  be  30nii  litres  in  eight  hours,  from  which  he  collected  100  c.  c.  of  fluid. 
A  distinct  ammonia  reaction  was  obtained  upon  the  addition  of  Nessler's  reagent. 
Nitrate  of  silver  failed  to  show  the  presence  of  chlorine. 

Its  reducing  power  upon  solution  of  permanganate  of  potash  showed  50  mg. 
of  oxygen  necessary  to  oxidize  one  litre  of  fluid,  or  15  mg.  in  24  hours,  which 
denotes  0.0017  mg.  per  litre  of  expired  air.  The  alkaloid  reaction  vvitli  AuCej, 
KI,  phosphomolybdate  of  potash,  gave  negative  lesults. 

He  expired  500  litres  through  150  c.  c.  of  a  1  [)er  cent,  solution  of  IICl — then 
evaporating  to  dryness  on  the  water-bath,  a  yellowish-brown  deposit  remained. 
This  deposit,  dissolved  in  distilled  water,  formed  a  fatty  layer  on  the  surface  of  the 
slightly  yellow  fluid.  The  whole  (pumtity,  1.5  g.,  was  warmed  to  the  body  tem- 
perature and  injected  under  the  skin  of  the  back  of  a  white  mouse  without  pro- 
ducing observable  symptoms.  This  fluid  had  a  distinct  odor  not  comparable  to 
anything. 

lie   next  confined  a  mouse  in  a  sealed  glass  vessel,  having  a  globe   attached 


12  THE  COMPOSITION  OF  EXPIRED  AIR, 

with  potash  solution  to  absorb  the  carbonic  acid ;  3200  expirations  of  air  were 
conducted  into  the  glass  vessel  dui'ing  the  three  hours — no  effect  noticeable.  In  a 
second  experiment  the  carbonic  acid  was  not  absorbed,  the  experiment  lasting  four 
hours — no  effect. 

He  repeated  the  "  Brown-Sequard  "  experiment,  using  white  mice  in  four  glass 
cages.  The  death  of  the  animals,  he  believes,  was  due  to  changes  in  the  tempera- 
ture and  the  accumulation  of  moisture  in  the  jars.  He  believes  the  protection 
afforded  by  HjSO^  in  Browu-Secpiard  and  d'Arsonval's  experiments  was  due  to  its 
abstraction  of  the  moistui-e  from  the  air.  An  acute  poisoning  through  the  organic 
matters  contained  in  the  expired  air  he  believes  to  be  impossiVjle,  or  at  least  as 
not  shown  by  anything  in  his  experiments. 

Rauer,  in  1893,  (32),  used  white  mice  confined  in  glass  vessels  of  about  1^ 
litres  capacity,  the  bottom  t>f  which  was  covered  with  oats.  The  coi'k  was  per- 
forated by  three  tubes :  one  of  these  passed  down  near  the  bottom  of  the  vessel 
and  served  for  the  entrance  of  the  air;  the  second  terminated  just  below  the  coi'k 
and  served  for  the  exit  of  air;  and  the  thii'd  extended  down  to  about  the  height 
of  the  animal  but  was  usually  closed,  this  was  only  used  for  the  removal  of  air  for 
its  chemical  examination.  .  In  the  beginning,  thermometers  and  hygrometers  were 
used  in  the  vessels,  but  they  were  found  to  be  unimportant  and  were  abandoned. 
The  whole  apparatus  was  connected  with  a  large  aspirator. 

In  an  experiment  with  five  animals  and  a  ventilation  of  four  litres  per  hour, 
the  carbonic  acid  was  found  to  amount  to  9.3  percent,  after  five  honrs.  In  another 
experiment  with  six  animals  and  with  a  ventilation  of  2^  litres  per  hour,  he  inserted 
four  absorption  tubes  with  soda-lime  between  the  last  two  jars,  and  a  Geissler  tube 
containing  concentrated  HgSO^  between  the  fourth  and  fifth.  The  sixth  animal 
remained  alive  while  the  fifth  died  earlier  than  the  fifth  animal  in  the  first  experi- 
ment. He  concludes  that  there  is  no  organic  poison  in  expired  air,  death  being 
due  to  the  excess  of  carbonic  acid  in  the  atmospheres  of  the  jars. 

Sanfelice,  in  1893,  (33),  reported  that  he  had  repeated  the  "  Hammond  " 
experiment,  using  a  flask  of  about  5  litres  capacity,  the  animal  dying  in  six  or 
seven  hours.  He  is  undecided  as  to  the  existence  of  a  volatile  expiratory  poison, 
though  he  thinks  that  other  factors,  for  instance,  heat  radiation,  have  an  important 
influence  upon  the  results. 

Liibbert  and  Peters,  in  1894,  (34),  reported  that  they  had  repeated  the  "Brown- 
S(^qnard  "  experiment,  placing  a  guinea-pig  in  each  of  a  series  of  four  flasks. 
Between  the  third  and  fourth  flasks  they  placed  a  combustion  tube  through  which 
the  air  coming  from  the  third  flask  was  conducted,  passing  over  red-hot  cupric 
oxide,  to  remove  the  organic  matter.     Before  reaching  the  fourth  flask,  the  air  was 


AND  ITS  EFFECTS  ITPON  ANIMAL  LIFE.  1 3 

again  cooled  by  coiuUictiug  it  tlirough  a  cylinder  surrounded  witli  ice.  In  this 
manner  ;dl  moisture  contained  in  the  air  was  condensed.  From  this  cylinder  the 
air  passed  through  a  series  of  twelve  U-tubes,  each  made  from  a  piece  of  tubing 
80  cm.  in  length  and  of  2  millimeters  internal  diameter.  During  its  passage 
through  these  U-tubes  the  air  assumed  a  temperature  of  about  18  °  C.  as  it  entei'ed 
tlie  fourth  flask.  The  I'esults  o])tained  by  this  arrangement  substantiated  the  con- 
clusions they  had  fornu'il  from  cunduc-ting  the  e.xperiment  in  the  oi'dinarx'  niaiinei-, 
that  the  cause  of  deatli  was  ti'aceable  to  the  high  per  cent,  of  carbonic  acid.  Tiie 
removal  of  the  organic  matter  by  combustion  failed  to  save  the  life  of  the  animal 
in  the  last  jar  when  the  carbonic  acid  had  inci'eased  to  11  or  12  per  cent.  After 
the  absor[>tion  of  the  carbonic  acid  by  means  of  soda-lime  the  last  animal  remained 
alive.  They  conclude,  therefore,  that  the  poisonous  expiratory  poison  of  Brown- 
Sequard  and  d'Arsonval  does  not  exist,  but  that  death  is  produced  by  the  excess 
of  carbonic  acid  in   the  flasks. 

Brown-Secpiard  and  d'Arsonval,  in  1894,  (35),  reported  further  experiments,  and 
at  the  same  time  gave  fuller  details  as  to  all  their  experiments  and  the  apparatus  em- 
ployed. They  had  inoculated  over  one  hundred  animals  with  the  condensed  fluid  of 
i-espiration  and  believed  in  the  tiuth  of  theii'  former  statements  as  firmly  as  ever. 
They  could  not  understand  the  failures  on  the  part  of  the  other  experimenters. 
They  emjijiatically  I'eaftirm  that  tlie  expired  lireath  of  man  and  animals  contains  a 
volatile  organic  poison  producing  the  results  reported  by  them,  and  tliat  these 
residts  are  not  produced  by  excess  of  carbonic  acid  or  deficiencv  of  oxygen  in 
the  air. 

From  the  foregoing  sununai}  of  the  reports  of  different  exjierinienters,  it  will  be 
seen  that  widely  different  results  have  been  i-eported  by  them,  but  that  the  majoi'ity 
of  the  later  investigators  agree  in  denying  that  the  exhaled  breatii  of  iiealthy 
human  beings  or  of  animals  contains  a  poisonous  organic  alkaloid,  or  any  poisonous 
product  other  than  carbonic  acid,  yet  in  any  case  positive  results  require  an  expla- 
nation which  shall  account  for  the  facts. 

Dii.  beegey's  experiments. 

The  first  experiments  made  by  Dr.  Bergey  were  to  ascertain  whether  the  con- 
densed moisture  of  air  expired  by  men  in  ordinary,  quiet  respiration,  contains  any 
particulate  organic  matters,  such  as  micro-oiganisms,  epithelial  scales,  etc.  The 
test  for  micro-oiganisms  was  made  by  having  an  adult  man  expire  for  from  twenty 
to  thirty  minutes  tlirough  sterilized  melted  gelatin,  which  was  then  preserved  as  a 
culture  for  from   twenty  to  thirty  days.     In  the  first  trial,  six,  and  iu  the  second 


14 


THE  COMPOSITION  OF  EXPIRKD  AIR. 


two  colonies  of  common  ;iir  orij;;inisms  (icvclopcd  ;  !)nL  wlicn  special  care  was  taken 
to  thoroughly  sterilize;  the  vessels  used,  the  I'esiilt  was  that  in  two  consecutive  trials 
the  gelatin  remained  sterile.  Ejiithelial  scales  and  other  jiarticulate  inatteis  wei'e 
sought  for  hy  condensing  the  vapor  of  the  exhaled  breath  and  examining  the  pi'o- 
duct  with  the  microscope,  with  and  without  tlie  use  of  stains.  In  six  preparations 
thus  examined  no  bacteiia  or  epithelial  cells  were  found.  Tliis  result  was  to  he 
expected,  since  neither  bacteiia  nor  wetted  particles  pass  into  the  air  from  the  sur- 
face of  fluids,  or  from  moist  surfaces,  unless  the  air  currents  ai'e  sufficiently  power- 
ful to  take  up  particles  of  the  liquid  itself  in  the  form  of  s^ira}-. 

Abbott  (36),  in  his  paper  on  "  Sewei-Gas,"  reports  some  experiments  made  to 
determine  the  possibility  of  conveying  micio-organisBis  from  licpiid  cultuie  media 
by  means  of  a  current  of  air  bubbling  through  such  media;  also  by  means  of 
t)rdinary  baker's  yeast  inoculated  into  media  containing  from  i  to  5  jter  cent,  of 
glucose.  No  ])acteria  were  carried  from  the  culture  by  the  ex[)]oding  air-bultbles 
produced  by  the  yeast,  but  a  cui'reut  of  aii'e(pial  to  3^  litres  in  six  luiurs,  bubbling 
through  a  liquid  culture,  carried  with  it  some  of  the  organisms  in  the  culture. 

The  determinations  of  ammonia  in  the  condensed  fluid  of  expii-ed  air,  the  esti- 
mation of  its  reducing  power  upon  solution  of  permanganate  of  potash,  and  its 
reacti(.)n  with  various  reagents  (see  Ap>pendix,  Section  II.),  were  made  with  fluids 
collected  from  a  healthy  man,  from  a  man  with  a  ti'acheal  fistula  fcillowing  excision 
of  the  lai-ynx,  the  expired  air  not  coming  in  contact  with  the  nnjuth  oi'  the  pharynx, 
and  from  a  man  suffering  from  well  marked  tuberculosis  of  the  lungs.  In  each 
case  the  amount  of  ammonia  and  of  albuminoid  ammonia  in  the  fluid  was  very 
small,  as  shown  by  Table  B  in  the  appendix,  the  average  being,  in  grams  per  liti'e 
of  fluid  : 


Healtliy  man 

Man  with  tracheal  fistula 
Consumptive 


.Mbuniinoid  Ammonia. 

.o8l 

.00036. 

.0034. 


The  oxidizable  matter  in  these  fluids,  as  shown  by  theii'  reducing  power  on  a 
solution  of  permanganate  of  potash,  was  detei'mined,  and  the  details  are  given  in 
Table  C  in  the  appendix.  The  average  results,  stated  in  milligrammes  of  oxygen 
consumed  per  litre  of  condensed  fluid,  are  as  follows:  Healthy  man,  10.72  ;  man 
with  tracheal  fistula,  13.49;  consumptive,  19.34.  The  high  average  for  the  man 
with  the  tracheal  fistula  is  due  to  a  single  observation,  for  which  the  figure  was 
24.916.     Omitting  this,  the  average  for  the  three  other  observations  would  be  9.68. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  15 

The  average  for  five  s[)eeiriieiis  of  fluid  condensed  from  the  expired  air  of  a 
healtiiv  ni.iii  four  iiours  after  lie  iiad  tal;en  a  meal  was  11.98,  while  the  average  for 
six  s[)eeimeMs  from  the  lueath  of  the  sauie  uiau  half  an  lioui'  after  the  meal  was 
i>nly  3.8().  For  two  specimens  from  the  same  man  collected  three  and  a  half  and 
four  hour.s  after  a  meal,  liut  just  after  the  mouth  had  been  thoroughly  rinsed  with 
warm  water,  the  average  was  2.4',).  These  results  indicate  that  the  ammonia  and 
oxidizable  oi'ganic  matter  in  the  condensed  iluid  were,  to  a  lai'ge  extent,  due  to 
products  of  decomposition  of  organic  matters  in  the  mouth.  The  well  known  fact 
that  the  amount  <>f  oxygen  absorbed  ami  of  caibonic  acid  given  oK  varies  accord- 
ing' to  whether  the  person  is  fasting  or  has  recently  taken  a  meal,  may  possibly 
be  ill  part  due  to  the  same  cause,  but  the  results  obtained  by  Birkhol/,  (87)  indi- 
cate that  it  can  only  be  in  part.  Rausome  (11)  reports  no  marked  difl'erence  iu 
the  amount  of  ammonia,  or  o(  oxidizable  organic  matter,  as  determined  by  the  per- 
manganate test,  contained  in  the  fluids  collected  from  the  exhaled  breath  soon  after 
a  meal  and  in  that  collected  from  a  fasting  person.  Ben  (-"SI  )  found  a  much  higher 
proportion  of  oxidizable  matter  in  the  fluid  condensed  from  his  own  breath  (50 
mg.  of  oxygen  re(piired  i)er  litre  of  fluid)  than  was  .found  iu  Dr.  Bergey's  experi- 
ments. His  results  indicated  the  exhalation  of  15  mg.  of  organic  matter  in  24 
hours,  the  corresponding  figure  from  Ransome's  results  being  20  mg.  About  12 
c.  c.  of  fluid  was  collected  from  about  .'585  litres  of  air  expii'ed  pei'  hour,  being 
nearly  equal  to  the  results  obtained  by  Beu  (31),  who  condensed  100  c.  c.  of  the 
fluid  from  three  cubic  metres  of  air.expired  in  eight  hours. 

Renk  (88,  p.  1(32)  gives  a  table  showing  that  in  an  average  quantity  of  9000 
litres  of  air  expired  in  a  day  by  a  healthy  man,  the  amount  of  moisture  may  be 
from  200  to  400  grammes,  depending  on  the  temperature  and  relative  moisture  of 
the  inspired  ail-.  With  ;iir  containing  5<l  per  cent,  of  moisture  inspired  at  25°  C, 
the  amount  of  moistui-e  is  293  grammes,  or  about  the  result  given  by  Beu,  referred 
to  above. 

Lehmann  and  Jesseu  (25)  found  that  between  3  and  4  mg.  of  oxygen  were 
recpiired  to  one  litre  of  fluid  to  effect  oxidation,  and  note  that  more  ammonia  was 
present  in  the  fluid  collected  from  a  person  with  decayed  teeth  than  in  that  ob- 
tained from  a  [lerson  whose  teeth  were  sound.  The  very  considerable  differences 
in  the  amounts  of  ammonia  and  of  oxidizable  matter  found  in  the  fluids  condensed 
from  expired  air  by  different  experimenters,  and  by  the  same  experimenter  in 
fluids  otjtained  from  the  same  person  at  different  times,  are  probably  due  to  sev- 
eral different  causes  and  their  combinations.  The  amount  of  fluid  condensed  per 
litre  of  expired  air  varies  from  .003  to  .004  c.  c.  The  soundness  and  cleanliness 
of  the  mouth  and  teeth  influeace  the  amount  of  ammonia  and  oxidizable  matter 


16  THE  COMPOSITION  OF  EXPIRED  AIR, 

expired.  Variations  in  tlie  amount  of  oi'tfanit-  nialtcr  contained  in  tlie  inhaled  air 
may  possil>ly  intinence  tlie  result,  l)ut  tiiis  influence  must  be  slight.  Ransome's 
I'esults  indicate  that  tlie  age,  health,  and  vigor  of  the  person  may  affect  the  amount 
of  organic  matter  exhaled,  and  Dr.  Bergey's  e.xperiments  with  the  fluid  obtained 
from  the  consumptive  patient  show  that  a  smallei-  pro[)ortion  of  ammonia  and  a 
largei'  amount  of  oxidizable  luatter  weve  present  in  it  than  in  the  fluid  collected 
from  a  hcallhy  man.  It  should  be  remembered,  also,  that  it  is  extremely  difficult 
to  obtain  accurate  results  in  quantitative  determinations  (_)f  such  very  minute 
amounts  of  ammonia  and  oxidizable  matters  as  are  found  in  expired  air,  and  a  pai't 
of  the  differences  in  results  obtained  is  no  doubt  due  to  unnoted  differences  in 
the  details  of  the  experiments. 

The  results  of  tests  foi'  the  presence  of  an  organic  alkaloid  in  the  condensed 
fluids  obtained  by  Dr.  Bergey  were  negative,  corres[)onding  to  those  reported  by 
Lehmann  and  Jessen  (25)  and  by  Beu  (31). 

The  I'esults  of  attempts  to  condense  the  moistui'e  of  the  air  in  the  hospital  ward 
(Apjiendix,  III.,  3)  were  not  satisfactory,  and  the  detei-minations  of  ammonia  in  the 
fluid  obtained  are  not  comparable,  except  that  they  show  that  the  placing  of  a  dust 
filter  in  front  of  the  condensing  apparatus  causes  a  maiked  reduction  in  the  propor- 
tion of  ammonia  in  the  condensed  fluid.  The  eva[)o]'ation  equalled  the  condensa- 
tion except  on  days  when  the  extei'ual  air  was  saturated  with  moisture,  hence  no 
moisture  was  collected  on  clear  days,  but  on  such  days  some  dust  ^^ai'ticles  may 
have  accumulated  in  the  aftparatus  which  had  no  filter. 

Some  experiments  wei'e  made  to  determine  the  amount  of  oxidizable  matters 
in  atmospheric  air,  the  results  of  which  are  given  in  Taljle  F,  in  the  appendix. 
These  results  differ  greatly,  some  showing  a  mere  trace  of  organic  matter,  others 
showing  an  amount  which  consumed  .204,  .340,  and  .558  grammes  of  oxj'gen  per 
1000  cbm.  of  aij-.  The  great  differences  in  the  amount  of  ammonia  in  air  found  by 
different  observers  as  tabulated  by  Renk  (38,  p.  40),  and  as  repiorted  by  Remseu 
(39),  Miss  Talbot  (40),  Nekam  (41),  Archarow  (42),  and  Abbott  (36),  while 
evidently  in  [lart  due  to  diffei'euces  in  metlnjds  of  experiment,  must  be  more  largely 
due  to  differences  in  the  amount  of  organic  dusts  in  the  air  in  different  places  or  in 
the  same  place  at  different  times,  than  to  differences  in  the  amount'  of  ammoniacal 
gases  or  organic  vapors  in  the  air,  and  the  same  is  true  with  regard  to  the  differ- 
ences in  the  amount  of  oxidizable  organic  matter  in  the  air  reported  by  Angus 
Smith  (12),  Carnelly  and  Mackey  (43),  and  others. 

Several  series  of  experiments  were  made  to  determine  the  nature  of  the  gaseous 
mixtures  in  which  small  animals  die  with  symptoms  of  asphyxia.  The  first  of  these 
series  were  repetitious  of  the  experiments  reported  by  Hammond  and  described 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  17 

above.  Mice  ami  sparrows  were  used.  The  details  are  given  in  tlie  Appendix 
IV.,  1,  and  the  residts  in  Table  Ct.  It  was  found  impossible,  by  Hammond's 
method,  to  absoil)  all  the  carbonic  acid  produced  by  au  animal,  and  it  will 
be  seen  by  Table  tr,  that  at  the  time  of  death  of  the  sparrows,  the  carbonic  acid  had 
increased  until  it  foi'med  from  12.27  to  14.08,  or  an  average  for  eight  experiments 
of  13.24  per  cent,  of  the  air,  while  the  oxj'gen  had  diminished  to  from  3.25  to  5.61, 
or  an  average  of  4.67  pi'r  cent,  of  the  air.  The  symptoms  observed  were  those  [pro- 
duced liy  insufficiency  of  ox3^gen,  and  there  was  no  evidence  that  death  was  due  to 
oi'gaiiic  matters  in  the  air.  The  duration  of  life  in  the  animals  confined  was  from 
thi'ce  to  six  hours,  being  much  longer  than  that  reported  by  Hammond  using  a 
slightly  smaller  vessel,  viz.  less  than  one  hour,  and  coi'responds  to  the  results  re- 
ported by  Sanfelice  (33),  who  found  that  the  animals  lived  from  six  to  seven  hours. 
AVlien  the  experiment  was  so  modified  that  all  the  carbonic  acid  was  removed  from 
the  air  breathed  by  the  animal — as  described  in  the  appendix,  the  animal  did  not 
die  in  seven  hours,  although  the  percentage  of  oxygen  had  been  reduced  to  18.35, 
as  shown  by  Table  li  in  the  a[ipeiidix.  These  experiments,  therefore,  furnish  no 
evidence  of  the  existence  of  an  organic  poison  in  the  expired  air,  but  the  method  of 
aVjsorbing  carbonic  acid  by  an  alkali  is  said  by  Bro^vn■Sequard  and  d'Arsonval 
(22)  to  change  the  organic  poison  which  they  claim  to  be  present,  and  hence  these 
experiments  are  not  conclusive  on  this  point. 

A  series  of  experiments  was  also  made  upon  mice  and  sparrows  to  determine 
the  time  required  to  produce  death  by  asphyxia  when  the  animal  is  confined  in  a 
jar  of  known  capacity,  when  no  provisi(Mi  is  made  for  removing  carbonic  acid  and 
moisture,  or  for  supplying  fresh  air,  and  also  to  determine  the  proportions  of  carbonic 
acid  and  of  oxygen  existing  in  the  enclosed  air  at  the  time  of  death.  In  connec- 
tion with  these  experiments  it  was  also  sought  to  determine  the  influence  which 
high  or  low  temperatures  of  the  air  would  have  on  the  result.  The  data 
deiived  from  these  expei-inients  are  shown  in  Table  I  in  the  Ai)pendix. 

A  mouse  weighing  21  grams,  placed  in  a  jar  of  1000  c.  c.  capacity  at  a  tem- 
perature of  30  °  C,  lived  four  hours  ;  in  a  jar  of  2000  c.  c.  capacity  a  similar  mouse 
lived  seven  and  a  half  hmns  ;  in  one  case  when  the  room  temperature  was  25.5°  C, 
in  another  case  when  the  room  temperature  was  5°C.  In  the  first  case  death 
occurred  when  the  amount  of  carbonic  acid  was  12,  and  that  of  the  oxygen  8.6  per 
cent,  of  the  mixtui-e;  in  the  .second  case,  the  pi'oportions  were  13.2  per  cent,  of  car- 
bonic acid  and  6.4  per  cent  of  oxygen  ;  and  in  the  third  case,  10  per  cent,  of  car- 
bonic acid  and  9.2  per  cent,  of  oxygen.  Thei'e  ai-e  considerable  differences  in  suscep- 
tibility to  the  effects  of  an  impure  atmosphere  in  individual  mice,  but  when  a  mouse 
is  placed  in  a  closed  jar  containing  ordinary  atmospheric  air,  the  time  required  to 


18 


THE  COMPOSITION  OF  EXPIRED  AIR, 


jiroduce  deatli  is  usually  tli.it  iviiuired  to  pi'ddnee  tlic  proportions  of  oarlionic  acid 
and  of  oxygen  indicated  above,  and,  hence,  is  in  pro[)oi-ti()n  to  the  size  of  the  jar. 
A  mouse  should  li\e  about  twice  as  long  in  a  jar  of  2000  c.c.  as  in  one  of  1000  c.  c, 
othei'  contiitioiis  as  to  tenqierature,  etc.,  being  the  same,  and  commencing  with 
oidinary  atmosplieric  air. 

The  (Uiration  of  life  in  the  expei'iinents  with  atmosfiheric  air  in  closed  vessels, 
making  due  allowance  for  variations  in  the  air  Nolume,  coincides  quite  closely  with 
the  dui'ation  of  life  in  the  "  Hammond  "  ex[ieriment.  The  air  analyses  at  death  of 
the  animals  in  the  two  forms  of  experiment,  also  gave  very  similar  results.  In 
comparing  the  I'esults  shown  in  Tables  G  and  I,  it  is  necessary  to  bear  in  min<l  tlie 
differences  in  the  size  of  the  jars  and  in  the  weight  of  the  animals  used  in  the  sev- 
eral experiments.  As  a  general  rule,  the  animal  dies  when  the  carbonic  acid  has 
increased  to  between  12  and  13  per  cent,  and  the  oxygen  has  diminished  to  be- 
tween 5  and  0  per  cent.  Is  death  due  to  the  increase  in  the  carl)ouic  acid,  or  to 
the  diminution  in  the  oxj'gen,  or  to  both  ? 

Some  data  foi-  answering  this  (|uestiou  are  presented  in  Table  L,  which  shows 
the  i-esults  obtained  by  placing  animals  in  gaseous  mixtures  containing  various  pro- 
portions of  carbonic  acid,  oxygen,  and  nitrogen.  The  animals  expei'imented  on 
were  mice,  I'ats,  rabbits,  guinea-pigs,  and  sparrows.  From  this  table  it  will  be  seen 
that  the  diminution  iu  oxygen  in  the  inspired  air  was  the  most  important  factor  in 
producing  death,  and  that  so  long  as  the  oxygen  is  present  in  the  proportion  of  6 
per  cent,  and  upwards,  carbonic  acid  may  be  present  to  the  amount  of  20  pei'  cent, 
without  causing  death.  When  the  carbonic  acid  forms  much  more  than  20  per 
cent,  of  the  mixture,  say  30  to  40  per  cent.,  the  oxygen  must  form  at  least  12  per 
cent,  to  [)i'eserve  life.  .  '• 

If  the  pi'02)ortion  of  oxygen  in  the  mixture  be  reduced,  the  dui'ation  of  life  is 
shortened,  as  will  be  seen  from  the  following  extract  from  Table  L: 


No. 

Weight 
grams. 

At  beginning  of 
experiment. 

At  end  of 
experiment. 

Duration  of 
life. 

Capacity  of 
jar. 

i8 

15 
17 

CO. 

O. 

N. 

CO. 

0. 

N. 

3I  hours. 
4i       " 
4h       " 

8 
9 

10 

o 
o 
o 

11-35 
11-35 
11-35 

88.65 
88.6s 
88.6s 

6.56 
7-43 
7-52 

4.14 
3-58 
316 

89-3 
89.0 
89.2 

2280  c.  C. 
2280      " 
2280      " 

In  these  experiments  the  proportion  of  oxygeu  was  reduced  to  about  one-half  of 
that  iu  the  normal  atmosphere,  and  the  dui'ation  of  life  was  also  reduced  about  one- 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  19 

balf.  Tlif  jars  were  a  little  larger  than  those  used  in  tin-  experiments  reported  iu 
Table  I.  The  proportion  of  oxygen  present  at  the  death  of  tiie  animal  was  between 
;5  and  4  per  cent.,  or  lower  tiiaii  in  the  cases  reported  in  Table  I,  while  the  car- 
bonic acid  had  increased  to  only  about  T  per  cent,  instead  of  12  per  cent,  as  in 
Table  I.  The  smaller  proportion  of  carbonic  acid  here  present  seems  to  have 
allowed  a  greater  reduction  in  the  proportion  of  the  oxygen.  These  I'esults  cor- 
respond with  those  obtained  with  mixtures  of  gases  by  Paul  Bert  (7,  page  518), 
who  concluded  that  carbonic  acid  when  iniiaU'd  is  really  a  poison,  and  with  the 
results  of  the  elaborate  researches  of  Friedljindcr  and  Ilerter  (44),  which  lead  to 
the  same  conclusion. 

In  this  connection  the  observations  of  Kichanlson  (8)  are  of  interest.  Ilis 
experiments  were  made  chietly  with  mice  placed  in  jars  having  a  capacity  vi  685  c.  c. 
In  such  a  jar  containing  ordinary  atmos})herie  air  at  12.8''  C,  a  mouse  weighing 
18.8  irrams  became  comatose  in  If:  hours,  which  is,  he  sa\s,  the  averacre  duration  of 
life  under  such  conditions.  At  a  temperature  of  6.6*^  C,  the  animal  dies  in  forty 
minutes.  In  an  atmosphere  of  pure  oxygen,  at  6.6°  C,  the  animal  will  live  only 
two-thirds  as  long  as  in  atmospheric  air,  while  at  a  temperatuie  of  21^  C.  it  will 
remain  conscious  for  thi'ee  hours  and  lives  twelve  houi-s,  and  at  10"  C.  it  remains 
conscious  for  two  hours  ami  lives  thi'ee  or  four  hours.  With  atmospheric  air, 
the  nmdifications,  he  says,  are  less  distinctly  marked. 

The  results  of  similar  e.\|ierinients  made  with  air,  and  with  different  mixtures 
of  gases,  at  different  temperatures,  are  given  in  Table  J  in  the  Apjiendix.  These 
results  show  that  the  duration  of  life,  in  confined  places,  is  influenced  to  a  very 
marked  degree  by  temperature,  ;ind  that  this  influence  is  independent  of  the  rich- 
ness of  the  air  iu  oxygen.  E.\[)eriments  Nos.  3  and  17  noted  in  Table  J  indicate 
that  an  atmosphere  consisting  of  90  per  cent,  of  oxygen  and  10  per  cent,  of  nitrogen 
does  not  support  life  quite  as  long  as  does  ordinary  atmospheiic  air  when  the  tem- 
perature is  0°  C,  while  at  a  temperature  of  50°  C.  the  atmosphere  rich  in  oxygen 
supports  life  much  longer  than  theordinary  atmosphere,  as  is  shown  by  experiments 
Nos.  5  and  15  in  the  table.  Tlie  gradual  rise  in  temperature  which  must  have 
taken  place  in  the  experiments  previously  referred  to,  was  probably  but  a  small 
factor  iu  the  results  obtained,  because,  as  shown  in  the  tables  for  those  experiments, 
the  duration  of  life  and  the  proportion  of  oxygen  present  at  death  bear  a  constant 
relation  to  each  other.     This  they  fail  to  do  in  the  "  Richardson  "  experiments. 

The  toleration  wiiicli  is  acijuired  l)y  an  animal  by  prolonged  sojourn  in  an 
atmosphere  which  is  gradually  becoming  richer  in  carbonic  acid  and  poorer  in 
oxygen,  makes  it  impossible  to  compai'e  the  results  as  to  duration  of  life  in  such 
experiments  with  the  results  of  experiments  in  which  the  animal  is  placed  at  once 


20  THE  COMPOSITION  OF  EXPIRED  AIR, 

iu  an  atmosphere  coutaiuing  abnormal  proportions  of  these  gases,  so  far  as  tlie 
effects  of  increase  of  carbonic  acid  and  diminution  of  oxygen  are  concerned,  but  it 
is  evident  from  tlie  results  reported  in  Tal>]es  I  and  J,  that  death  does  not  occur  in 
atmospheres  in  which  the  carbonic  acid  does  not  exceed  10  [)er  cent,  unless  the 
oxygen  is  reduced  to  below  7  per  cent,  of  the  mixture. 

A  series  of  experiments  was  made  by  injecting  into  animals  the  fluid  con- 
densed from  the  air  expired  by  healthy  persons  and  by  a  man  with  a  tracheal 
fistula,  from  whom  it  was  possible  to  obtain  such  fluid  without  contamination  from 
the  exhalations  from  the  mouth.  The  details  of  these  experiments,  and  of  the 
results  obtained,  are  given  in  the  Ap2)endix,  VI.  The  injections  were  made  into 
the  general  circulation  in  rabbits,  and  into  the  pei'itoneal  cavities  of  rabbits,  guinea- 
pigs,  and  white  rats,  following  the  methods  employed  by  Brown-Sequaixl  and 
d'Arsonval  (15)  and  by  v.  Hofmann-Wellenhof  (23).  The  number  of  animals 
inoculated  with  the  condensed  fluid  of  respiration  was  thirteen,  in  four  sets.  The 
fluid  was  collected  with  the  greatest  care  in  a  sterilized  appai'atus ;  subsequent  cul- 
tures made  from  it  indicating  that  it  was  sterile.  It  was  waimed  to  about  35°  C, 
before  injection.  The  proportion  injected,  as  compared  with  the  body  weight  of 
the  animals,  was,  in  some  instances,  less  than  that  used  by  Brown-Sequard  and 
d'Arsonval,  in  others  greater  than  the  smallest  quantities  used  by  them  with  fatal 
effects.  The  results  obtained,  with  the  amount  of  fluid  injected  iu  each  case,  are 
shown  iu  Table  K,  given  iu  the  Appendix. 

In  most  of  the  animals  no  observable  disturbance  of  health  was  produced,  nor 
did  this  condition  alter  iu  the  course  of  several  months  dui-ing  which  they  were 
kept  under  observation.  One  rabbit  died  thirty-two  days  after  having  received  an 
injection  into  its  peritoneal  cavity  of  5  c.c.  of  fluid  condensed  from  the  breath  of  a 
man  with  tracheal  fistula.  The  results  of  'post-moi'tem  examination  showed  focal 
necrosis  in  the  liver,  but  no  ecchymoses  and  hemorrhages  in  the  lungs  and  intes- 
tines, such  as  ai'e  reported  as  a  characteristic  result  of  such  injections  by  Brown- 
Sequard  and  d'Arsonval.  Three  other  rabbits  which  had  received  injections  of 
the  condensed  fluid,  aud  had  remained  apparently  perfectly  well  fi'om  six  weeks  to 
seven  months,  were  killed  and  careful  post-mortem  examinations  made.  The  I'esults 
of  these  examinations  showed  that  there  was  no  special  disease  or  degeneration  in 
the  organs  of  these  animals. 

The  results  of  this  series  of  experiments  are,  thei'efore,  in  accord  with  those 
reported  by  v.  Hofmann-Wellenhof  (23),  and  indicate  that  fluid  condensed  from 
the  pulmonary  exhalations  of  man  has  no  toxic  or  specially  injurious  effect  when 
injected  into  animals,  and  that  there  is  no  evidence  that  such  fluid  contains  an 
organic  poison. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  21 

Tlie  attempt  to  collect  coiuleiisetl  moisture  fiom  the  air  of  tlie  hospital  ward 
was  1)11 1  partially  successful,  as  lias  been  stated  above,  aud  a  sufficient  amount  of 
the  fluid  to  make  injection  expei'imeuts  was  not  directly  oljtained.  To  overcome 
this  difficulty  the  air  of  the  ward  was  drawn  over  sterilized  glycerine  wliich  was 
then  ililuted  with  distilled  watei',  and  the  product  injected  into  animals.  The  re- 
sults are  shown  in  Table  E  in  the  Ajjpendix.  Three  of  the  animals  thus  injected 
died  between  four  and  six  weeks  later,  but  t\\Q  post-vwrtem  examinations  failed  to 
show  any  clear  connection  between  the  injection  and  the  fatal  result.  As  it  was 
shown  that  the  fluid  collected  and  the  dust  iu  the  ward  contained  several 
species  of  bacteiia,  including  pathogenic  forms,  it  was  to  be  expected  that  more 
definite  results  would  have  been  obtained,  but  the  power  of  the  cells  and  tissues  to 
resist  the  pathogenic  oi'ganisms  was  sufficient  to  prevent  their  action  in  each  case, 
except,  perhaps,  in  one,  in  which  the  abscess  produced  may  have  been  due  to  p>yo- 
genic  bacteria  in  the  injected  fluid. 

A  number  of  experiments  were  made  in  which  animals,  in  a  series  of  Jaell  jai'S, 
Avere  caused  to  breathe  air  which  became  more  contaminated  with  the  products  of 
respiration  as  it  passed  through  the  series,  being  a  repetition  of  the  experiments  of 
Brown-Sequard  and  d'Arsonval.  The  form  of  the  apparatus  used,  and  the  details 
as  to  the  results  obtaiued  in  each  of  the  thiity-three  experiments  of  this  kind,  are 
given  in  the  Appendix,  VII.  These  experiments  were  performed  on  spariows, 
mice,  guinea-pigs,  and  i-abbits. 

It  was  veiy  difficult  to  keep  the  apparatus  absolutely  air-tight,  and,  no  doubt, 
some  of  the  discrepancies  iu  the  results,  at  least  for  the  earlier  experiments,  are  due 
to  slight  leakage  of  air  through  some  one  or  more  of  the  numerous  joints.  The  more 
concordant  results  in  the  later  experiments  indicate  that  these  defects  had  been 
obviated. 

In  the  great  majority  of  cases  death  was  evidently  due  to  the  diminution  in 
the  oxygen  and  iuci'ease  in  the  carbonic  acid — the  proportions  of  these  gases 
present  in  tlie  jar  when  an  animal  died  being  about  the  same  as  in  the  experiments 
reported  in  Table  I,  /.  <?.,  the  oxygen  was  reduced  to  between  4  and  6  per  cent,  and 
the  carbonic  acid  increased  to  from  12  to  14  per  cent.  The  luode  of  death  of  the 
animals  Wiis  similar  to  that  observed  in  slow  asphyxi;i,  aud  the  results  of  careful 
j^as^/wo/'/t'ffi  examination  and  microscopic  investigation  do  not  indicate  the  effects  of 
any  oi-ganic  poison. 

The  insertion  of  absorption  tubes  containing  caustic  alkalies  between  the  bell 
jars,  to  absorb  the  carbonic  acid,  as  in  experiments  Nos.  6  to  14,  and  of  concentrated 
sul[ihuric  acid,  as  in  experiments  Nos.  15,  18,  and  19,  did  not  give  results  corre- 
sponding to  those  reported  by  Brown-Sequard  and  d'Arsonval. 


22  THE  COMPOSITION  OF  EXPIRED  AIR, 

In  tliese  experiments  the  aninmls  were  in  an  atmosphere  of  less  pressure  tlian 
the  external  air,  the  diminntion  anionnting  usually  to  about  '2  nun.  of  mercury,  liut 
there  is  no  reason  to  su[)pose  that  this  exerted  any  inHnence  upon  the  I'esnlts  obtained. 

Experiments  Nos.  17,  18,  and  19  show  that  the  mice  became  habituated,  to  a 
certain  extent  at  least,  to  the  conditions  under  which  they  were  placed,  and  could 
live  in  an  atmos[)hei'e  which  was  almost  immediately  fatal  to  a  fresh  mouse  placed 
in  it.  This  had  already  been  demonstrated  by  Bernard  (5).  In  the  case  of  several 
mice,  this  power  to  resist  the  f(jul  atinos[)liere  was  preserved  foi'  from  three  to  eight 
days  after  they  had  been  I'emoved  from  the  jar,  so  that  they  had  a  certain  degree 
of  permanent  immunity  (See  experiment  IS,  C).  Experiments  Nos.  20  to  28  were 
made  to  see  if  it  was  possible  todeveh)p  such  an  immunity,  and  the  results  obtained 
indicate  sucla  a  possibility,  but  further  investigation  will  be  necessary  to  settle  this 
impoi'tant  point.  At  present  it  is  uncertain  to  wliat  extent  tlie  immunity  observed 
in  a  few  mice  was  possessed  by  them  Ijefore  they  were  ex[)erimented  on,  or  was 
produced  by  their  first  exposures  to  the  vitiated  atmospheres. 

From  the  data  accumulated  with  reference  to  the  composition  of  the  atmos- 
phei'e  in  these  bell  jars  by  repeated  analyses  at  short  intervals,  compared  with  the 
results  reported  by  Brown-Secpiard  aud  d'Arsonval,it  seems  probable  that  the  cases 
in  which  tlie  last  animal  in  the  series  survived  some  of  the  othei's,  and  a  low  per- 
centage of  cai'bonic  acid  was  found  in  the  jar,  should  be  attributed  entirely  to  de- 
fects either  in  methods  of  aii'  analyses  or  in  the  apparatus,  or  in  both.  If,  however, 
the  life  of  the  last  animal  was  a{)pareDtIy  saved  by  HoSO^  in  Dr.  Bergey's  experi- 
ments, it  was  due  to  leakage  in  the  connections  fi-om  the  increased  resistance  caused 
by  the  interposition  of  the  absorption  tube.  This  is  an  important  fact,  which  is 
in  direct  opposition  to  the  theory  of  Bro\vn-Scquard  aud  d'Arsonval  with  j-egard  to 
the  influence  of  the  Hg  SO^  in  the  absoi'ption  tubes.  The  great  diflferences  in 
individual  susceptibility  of  different  animals  must  also  be  taken  into  account  in 
considering  the  results  of  these  experiments;  for  example,  in  experimentNo.il, 
spai-row  No.  4  dieil  when  the  percentage  of  oxygen  was  9.34,  and  that  of  carbonic 
acid  was  only  2.79,  while  No.  5  lived  until  the  percentage  of  oxygen  was  I'educed 
to  3.53.  In  some  mice  there  seems  to  be  a  very  considerable  immunity  against  the 
asphyxiating  effect  of  an  atmospheie  poor  in  oxygen  and  rich  in  carbonic  acid. 

The  duration  of  life  of  individual  animals  in  experiments  of  this  kind  depends 
upon  the  size  of  the  bell  jars  in  relation  to  the  size  of  the  animal,  on  the  amount  of 
fresh  air  supplied,  on  conditions  of  temperature  aud  moisture,  and  on  individual 
peculiarities  of  the  animal — and  it  seems  probable  that  variations  in  these  factors 
will  account  for  the  diifei'eut  results  obtained  by  different  experirnenters.  The 
symptoms  in  the  animals  which  died  were  those  of  death  by  slow  asphyxia. 


AXD  ITS  EFFECTS  UPON  ANIMAL  LIFE.  23 

In  exiieriment  No.  3:\,  with  a  series  of  six  rabbits  confined  for  foity-two  clays, 
tilt-  [iruportion  of  oarl)onic  acid  in  the  last  two  jars,  for  the  greater  part  of  the 
time,  was  between  4  and  7  jier  cent,  and  tliat  of  o.\\'gen  between  1'2  and  Ki  per  cent. 
None  of  the  aninnd-s  died  or  were  serionsly  ill.  Those  in  the  first  three  and  in  the 
fifth  Jar  gained  in  weight,  those  in  the  fonith  and  sixth  lost  slightly  in  weight. 

The  residts  of  lilood-corpuscle  counts  made  for  five  of  tiiese  animals  at  tlie  close 
of  the  experiment,  and  again  tliirtv-eight  days  afterward,  show  an  average  increase 
during  this  period  of  158,600  red,  and  .'>,  10(i  white  corpuscles  per  cultic  millimetre, 
an  aniniiiit  wiiicii  has  little  significance.  Microcytes  were  found  in  the  blood  of  the 
ani  mals  immediately  after  the  experiment,  l)ut  noue  were  found  thirty-eight  days  later. 

The  organs  of  a  numbei'of  the  animals  that  died  in  these  expeiiments  were  pre- 
served in  alcohol  and  examined  microscopically.  The  changes  noted  post  mortem 
were  those  of  pmfound  venous  congestion  nt'  .ill  the  internal  organs.  The  lungs 
were  fretpientU'  so  charged  with  venous  blood  that  the  portions  preserved  for 
microscopic  examination  failed  to  float  in  water.  The  right  side  of  the  lieart  was 
usually  dilated  with  a  large  firm  venous  clot,  the  left  ventricle  w-as  in  most  instances 
contracted.  The  liver,  on  incision,  bled  fi'eely,  as  did  also  the  kidneys  and  spleen, 
the  blood  being  quite  dark  and  venous.  All  the  capillaries  were  unusuall)'  pi'omi- 
nent,  being  filled  with  venous  blood;  this  was  particularly  noticeable  in  the  small 
intestine,  and  in  the  luembi'anes  of  the  bi'ain. 

Microscopic  examination  of  the  organs  presented  a  picture  coinciding  with  the 
gvoss post-iiiortetii  a})pearances.  In  the  lungs  the  capillaries  wei'e  found  to  be  dis- 
tended with  blood,  occluding  in  many  cases  the  lumen  of  the  alveoli  and  air  cells, 
and  presenting  a  typical  jiicture  of  passive  hyj)eiwmia.  In  the  liver,  kidneys,  and 
spleen,  as  well  as  in  the  intestines,  the  capillaries  were  likewi.se  overloaded  with 
blood.  Patliological  changes  wei'e  but  rarely  noted,  and  some  of  these,  such  as 
slight  proliferation  of  connective-tissue  elements  betw^een  the  tubules  of  the  kidney, 
and,  in  rarer  instances,  in  the  inter-lobular  spaces  of  the  liver,  are  such  as  are  occa- 
sionally found  in  animals  which  have  not  been  subjected  to  such  conditions,  and 
may,  therefore,  have  existed  in  the  animals  at  the  beginning  of  the  experiment.  All 
the  changes  which  were  constantly  present  may  propeily  be  attributed  to  the  action 
of  the  carbonic  acid  and  the  low  percentage  of  oxygen  in  tlie  atmosphere,  intei'feriug 
with  the  cii'culation  and  aeration  of  the  blood.  The  lesions  reported  by  Brown- 
Secpiard  and  d'Arsonval  as  characteristic  in  such  cases  were  not  seen.  No  focal 
necroses  or  peculiar  uniform  degenei'ative  changes  were  found.  The  results  of  these 
experiments,  therefore,  do  not  agree  with  those  reported  by  Brown-Sequard  and 
d'Ai"sonval — and  furnish  no  evidence  of  the  existence  of  an  organic  poison  in  the 
air  expired  by  animals. 


24  THE  COMPOSITION  OF  EXPIRED  AIR, 

CONCLUSIONS. 

I.  Tlie  it'sults  obtaiiieil  in  this  reseairli  indicate  tliat  in  air  exj>ire(l  by 
healthy  mice,  sparrows,  rabbits,  guinea-[)igs,  or  men,  tiicn;  is  no  peculiar  organic 
matter  wliicli  is  poisonous  to  the  animals  mentioned  (excluding  man),  or  which 
tends  to  [)rodin'e  in  these  animals  any  s[)ecial  foi'ni  of  disease.  The  injurious 
effects  of  such  air  observed  appeared  to  be  due  entircdy  to  the  diminution  of 
oxygen,  oi'  the  increase  of  carbonic  acid,  or  to  a  combination  of  these  two  factors. 
They  also  make  it  very  improbable  that  the  minute  (quantity  of  oi'ganic  matter 
contained  in  the  air  expired  from  human  lungs  has  any  deleterious  influence  u[)on 
men  who  inhale  it  in  ordinary  rooms,  and,  hence,  it  is  probably  unnecessary  to 
take  this  factor  into  account  in  providing  for  the  ventilation  of  such  rooms. 

II.  In  oi-dinary  quiet  respiration,  no  bacteiia,  e[)ithelial  scales,  or  particles  of 
dead  tissue  are  contained  in  the  expired  air.  In  the  act  of  coughing  or  sneezing, 
such  organisms  or  particles  may  probably  be  thrown  out. 

III.  The  minute  (juantity  of  ammonia,  or  of  combined  nitrogen,  oi-  other 
oxidizaljle  matters,  found  in  the  condensed  moisture  of  human  breath  appears  to 
be  largely  due  to  products  of  the  decomposition  of  organic  matter  which  is 
constantly  going  on  in  the  mouth  and  pharynx.  This  is  shown  by  the  effects  of 
cleansing  the  mouth  and  teeth  upon  the  amount  of  such  matters  in  the  condensed 
moistui-e  of  the  breath,  and  also  by  the  differences  in  this  respect  between  the  air 
exhaled  through  a  ti'acheal  fistula  and  that  expired  in  the  usual  way. 

IV.  The  air  in  an  inhabited  room,  such  as  the  hospital  ward  in  which 
experiments  were  made,  is  contaminated  from  many  sources  besides  the  expii'ed 
air  of  the  occupants,  and  the  most  important  of  these  contaminations  are  in  the 
form  of  minute  particles  or  dusts.  The  experiments  on  the  air  of  the  hospital 
ward,  and  with  the  moisture  condensed  therefrom,  show  that  the  greater  part  of 
the  ammonia  in  the  air  was  probably  connected  with  dust  particles  which  could 
be  removed  by  a  filter.  They  also  showed  that  in  this  dust  there  were  micro- 
organisms, including  some  of  the  bacteria  which  produce  inflammation  and 
suppuration,  and  it  is  probable  that  these  were  the  only  really  dangerous  elements 
in  this  air. 

V.  The  experiments  in  which  animals  were  compelled  to  breathe  air  vitiated 
by  the  [)i'oducts  of  either  theii'  own  respii'ation  or  by  those  of  other  animals;  or 
\ve)'e  injected  with  fluid  condensed  from  expired  air,  gave  I'esults  contrary  to  those 
reported  by  Hammond,  by  Bi-own-Sequard  and  d'Arsonval,  and  by  Merkel,  but 
corresponding  to  those  reported  by  Dastre  and  Loye,  RussoGiliberti  and  Alessi, 
Hofmann-Wellenhof,  Ilauer,  and  other  experimenters  referred  to  in  the  preliminary 
historical    sketcli    of    this    report,    and    make    it    improbable    that    there    is 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  25 

any  peculiar  volatile  poisonous  matter  in  the  air  expii-ed  by  healthy  men  ami 
animals,  other  than  carbonic  acid.  It  must  be  borne  in  mind,  however,  that  the 
results  of  such  experiments  upon  animals  as  are  referred  to  in  this  repoi't  may  be 
applicable  only  in  pai't  to  liuiiian  beings.  It  does  not  necessarily  follow  that  a 
man  would  not  be  injured  by  continually  living  in  an  atmosphere  containing  2 
parts  per  1000  of  carbonic  acid  and  other  products  of  respiration,  of  cutaneous 
excretion,  and  of  putrefactive  decomposition  of  oi-ganic  matters,  because  it  is  found 
that  a  mouse,  a  guinea-pig,  or  a  rabbit,  seems  to  suffer  no  ill  effects  from  living 
under  such  conditions  for  sevei'al  days,  weeks,  or  mouths,  but  it  does  follow  that 
the  evidence  wliicli  has  heretofore  been  supposed  to  demonstrate  the  evil  effects  of 
bad  ventilation  upon  human  health  should  be  carefully  scrutinized. 

VI.  The  effects  of  reduction  of  ox\'gen  and  inci'ease  of  cai'bonic  acid  to  a 
certain  degree  appear  to  be  the  same  in  artificial  mixtures  of  these  gases  as  in  air  in 
which  the  change  of  proportion  of  these  gases  has  been  produced  by  respii-ation. 

VII.  The  effect  of  liabir,  wliicii  may  enable  au  animal  to  live  in  an  atmos- 
phere in  which,  by  i^natliial  change,  the  proportion  of  oxygen  has  become  so  low 
and  that  of  the  carbonic  acid  so  hi<i;h  that  a  similar  animal  brought  from  fi'esh  air 
into  it  dies  almost  immediately,  has  been  observed  before,  but  we  are  not  aware 
that  a  continuance  of  this  immunity  produced  by  it  had  been  previously  noted. 
The  experiments  reported  in  the  Appendix,  VII.,  17  to  28,  show  that  such  an 
imnumity  maj^  either  exist  normally  or  be  produced  in  certain  mice,  but  tiiat  these 
cases  ai'e  veiy  exceptional,  and  it  is  very  desirable  that  a  special  research  should 
be  made  to  determine,  if  possible,  the  conditions  upon  which  such  a  continuance  of 
immunity  depends. 

\'11I.  An  excessively  high  or  low  temperature  has  a  decided  effect  upon  the 
production  of  asphyxia  by  diminution  of  oxygen  and  increase  of  carbonic  acid. 
At  high  temperatures  the  respiratory  centres  are  affected,  where  evaporation  from 
the  skin  and  mucous  surfaces  is  checked  by  the  air  being  saturated  with  moisture; 
at  low  temperatures  the  consumption  of  oxygen  increases,  and  the  demand  for  it 
becomes  more  urgent. 

So  far  as  the  acute  effects  of  excessively  foul  air  at  high  tempei-atures  are 
concerned,  such,  for  example,  as  appeared  in  the  Black  Hole  at  Calcutta,  it  is 
probable  that  they  are  due  to  substantially  the  same  causes  in  man  as  in  animals. 

IX.  The  proportion  of  increase  of  carbonic  acid  and  of  diminution  of  oxygen, 
which  has  been  found  to  exist  in  badly  ventilated  churches,  schools,  theatres,  or 
barracks,  is  not  suflSciently  great  to  satisfactorily  account  for  the  great  discomfort 
which  such  conditions  produce  in  many  persons,  and  there  is  no  evidence  to  show 
that  such  an  amount  of  change  in  the  normal  proportion  of  these  gases  has  any 


26  THE  COMPOSITION  OF  EXPIRED  AIR, 

iiitlueiice  upon  the  iiicroiise  of  disease  and  deatb-rates  wliicli  statistical  evidence  has 
shown  to  exist  anioiig  jiersons  living  in  crowded  and  unventilated  rooms.  The 
Report  of  the  Comniissioners  appointed  to  in(iiiire  into  the  regulations  affecting  the 
sanitary  conditions  of  the  IJritish  Army  (1),  pi'operly  lays  great  stress  on  the  fact 
that  in  civilians  at  soldiers'  ages,  in  twenty-four  large  towns,  the  death-rate  per 
1000  was  n.9,  while  in  the  foot-guards  it  was  20.4,  and  in  the  infantry  of  the  line 
17.9,  and  showed  that  this  difference  was  mainly  due  to  diseases  of  the  lungs 
occurring  in  soldiers  in  crowded  and  unventilated  barracks.  These  observations 
have  since  been  repeatedly  confirmed  by  statistics  derived  from  other  armies,  from 
pi'isons,  and  from  the  death-rates  of  persons  engaged  in  diffei'ent  occupations,  and, 
in  all  cases,  tubercular  disease  of  the  lungs  and  pneumonia  aie  the  diseases  which 
are  most  prevalent  among  persons  living  and  working  in  unventilated  rooms, 
unless  such  persons  are  of  the  Jewish  race.  But  consumption  and  pneumonia  are 
caused  by  specific  bacteria,  which,  for  the  most  part,  gain  access  to  the  air-passages 
by  adhering  to  particles  of  dust  which  are  inhaled,  and  it  is  probable  that  the 
greater  liability  to  these  diseases  of  persons  living  in  crowded  and  unventilated 
rooms,  is,  to  a  lai'ge  extent,  due  to  the  special  liability  of  such  rooms  to  become 
infected  with  the  germs  of  these  diseases.  It  is,  however,  by  no  means  demon- 
strated, as  yet,  that  the  only  deleterious  effect  which  the  air  of  crowded  barracks  or 
tenemeut-honse  rooms,  or  of  foul  courts  and  narrow  streets,  exerts  upon  the  persons 
who  breathe  it,  is  due  to  the  greatei-  number  of  [)athogenic  micro-organisms  in  such 
localities.  It  is  tpiite  possible  that  such  impure  atmospheres  may  affect  the  vitality 
and  the  bactericidal  powers  of  the  cells  and  fluids  of  the  upper  air-passages  with 
which  they  come  in  contact,  and  may  thus  predispose  to  infections,  the  potential 
causes  of  which  are  almost  eveiywhere  present,  and  especially  in  the  upper  air- 
passages  and  in  the  alimentarj'  canal  of  even  the  healthiest  persons,  but  of  this  we 
have,  as  yet,  no  scientific  evidence.  It  is  very  desii'able  that  researches  should  be 
made  on  this  point. 

X.  The  discomfort  produced  by  crowded,  ill-ventilated  rooms  in  persons  not 
accustomed  to  them  is  not  due  to  the  excess  of  carbonic  acid,  nor  to  bacteria,  nor, 
in  most  cases,  to  dusts  of  any  kind.  The  two  great  causes  of  such  discomfort, 
though  not  the  only  ones,  are  excessive  temperature  and  unpleasant  odors.  Sucli 
I'ooms  as  those  referred  to  are  generally  overheated,  the  bodies  of  the  occupants, 
and,  at  night,  the  usual  means  of  illumination,  contributing  to  this  result. 

The  cause  of  the  unpleasant,  musty  odor  which  is  perceptible  to  most  persons 
on  passing  from  the  outer  air  into  a  crowded,  unventilated  room  is  unknown;  it 
may,  in  part,  be  due  to  volatile  products  of  decomposition  contained  in  the  expired 
air  of  persons  having  decayed  teeth,  foul  mouths,  or  certain  disorders  of  the  diges- 


AND  ITS  EFFECTS  XJPON  ANIMAL  LIFE.  27 

tive  apparatus,  and  it  is  iluc,  in  part,  to  volatile  fatty  acids  given  off  witb,  or 
produced  from,  the  excretions  of  the  skin,  and  from  clothing  soiled  with 
such  excretions.  It  may  i)roduce  nausea  and  other  disagreeable  sensations  in 
specially  susceptible  persons,  but  most  men  soon  become  accustomed  to  it,  and 
cease  to  notice  it,  as  they  will  do  with  regard  to  the  odor  of  a  smoking-car,  or  of  a 
soai)  factory,  after  they  have  been  for  some  time  in  the  place.  The  direct  and 
indirect  effects  of  odors  of  various  kinds  upon  the  comfort,  .-md  perhaps  also  upon 
the  health,  of  men  are  nuu-e  considerable  than  would  be  indicated  i)y  any  tests 
now  known  for  determining  the  nature  and  quantity  of  the  matters  w  Inch  give  rise 
to  them.  The  remarks  of  Renk  (38,  p.  174)  upon  this  point  merit  consideration. 
Cases  of  fainting  in  crowded  i-ooms  usually  occur  in  women,  and  are  connected 
with  defective  respiratory  action  due  to  tight  lacing  or  other  causes. 

Other  causes  of  discomfort  in  rooms  heated  l)y  furnaces  or  by  steam  are  exces- 
sive dryness  of  the  air,  and  the  presence  of  small  quantities  of  carbonic  oxide,  of 
illuminating  gas,  or  of  arsenic  derived  from  the  coal  used  for  heating. 

XI.  The  results  of  this  investigation,  taken  in  connection  with  the  results  of 
other  recent  reseai'ches  sununarized  in  this  report,  indicate  that  some  of  the  theoiies 
upon  which  modern  systems  of  ventilation  are  based  are  either  without  foundation 
or  doubtful,  and  that  the  problem  of  securing  comfoi't  and  health  in  inhabited 
I'ooms  requires  the  consideration  of  the  best  methods  of  preventing  or  disposing  of 
dusts  of  various  kinds,  of  properly  regulating  temperature  and  moistui'e,  and  of 
preventing  the  entrance  of  poisonous  gases  like  carbonic  oxide  derived  from  heat- 
ing and  lighting  apparatus,  rather  than  upon  simply  diluting  the  air  to  a  certain 
stanilard  of  propoi'tion  of  carbonic  acid  present. 

It  would  be  very  unwise  to  conclude,  from  the  facts  given  in  this  report,  that 
the  standards  of  air  supply  for  the  ventilation  of  inhabited  I'ooms,  \vliich  standards 
are  now  generally  accepted  by  sanitai'ians  as  the  result  of  the  work  of  Pettenkofer, 
De  Chaumont,  and  others,  ai'e  much  too  large  under  any  circumstances,  or  that  the 
differences  in  health  and  vigor  between  those  who  spend  the  greater  part  of  their 
lives  in  the  open  air  of  the  country  hills,  and  those  who  live  in  the  city  slums,  do 
not  depend  in  any  way  upon  the  diffei-ences  between  the  atmospheres  of  the  two 
localities  except  as  regards  the  number  and  character  of  micro-organisms. 


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die  Wirkung  der  Kohlensaure  anf  den  thieris- 
chen  Organismus.  Ztschr.  f.  physiol.  Chera., 
Strassb.,  1878-9,  II,  99-148. 


APPENDIX. 


Details  of  methods  employed,  and  results  obtained,  in  experiments  upon  the 

effects  of  expired  air. 


David  Hendricks  Bergey,  B.  S.,  M.D. 


(The  numbers  in  parentheses  refer  to  the  bibliographical  list  appended  to  the  report.) 

I. — Four  experiments  were  made  to  determine  whether  the  air  expired  by  man  contains  micro- 
organisms.    The  results  are  shown  in  the  following  table. 

Table  A. 


No. 

Date. 

Culture 
medium. 

Amount  of 

medium. 

Time  in 
breathing. 

Number  of 
colonies. 

Time  under 
observation. 

Remarks. 

I 

1893 
Dec.  29 

Gelatin. 

150  c.c. 

30  min. 

6 

Days. 
3° 

Common  air  organisms. 

2 

1894 
Jan.   10 

u 

ft            u 

n           t( 

2 

30 

U                   ((                          It 

3 

Feb.    7 

" 

<(         (( 

H             11 

0 

30 

Sterile. 

4 

Mch.    3 

1( 

((         11 

20    " 

0 

20 

(( 

In  these  experiments  the  expired  breath  was  conducted  through  melted  gelatin  contained  in  the 
apparatus  shown  in  Fig.  i,  for  20  to  30  minutes.  The  gelatin  was  then  hardened  by  rolling  the  flask 
in  a  shallow  basin  containing  ice-water,  thus  distributing  the  culture  in  a  thin  layer  over  the  bottom 

33 


34 


THE  COMPOSITION  OF  EXPIRED  AIR, 


Fig.  I. — Apparatus 
for  detennining  the 
pressure  of  bacteria 
in  expired  breath. 


ind  sides  of  the  flask.  Tliese  cultures  were  kept  under  observation  for  20  to  30  days.  About  150 
c.  c.  of  the  gelatin  was  used  for  each  experiment.  The  glass  tube,  b,  of  the 
apparatus  used,  which  served  for  the  entrance  of  the  expired  air,  was  inserted 
far  enough  to  just  impinge  on  the  fluid  culture  medium  in  the  flask,  so  that  the 
air  produced  a  slight  agitation  of  the  fluid   in  passing  through  the  apparatus. 

Description  of  the  apparatus  used  for  determining  the  presence  of  bacteria 
in  expired  breath,  Fig.  1.:  «,  represents  a  half  litre  Erlenmeyer  flask  closed  with 
a  rubber  stopper  having  two  openings.  Each  of  these  openings  is  closed  by  a 
glass  tube  bent  at  right  angles  above  the  stopper. 

/'.  represents  the  longer  glass  tube  which  reaches  nearly  to  the  bottom  of 
the  flask.  This  tube  has  a  small  bidb-shaped  enlargement  blown  into  its  upper 
end,  which  serves  to  retain  any  saliva  that  might  flow  into  the  tube.  This 
tube  serves  as  the  mouthpiece  through  which  the  air  enters  the  apparatus.  When  not  in  use,  the 
mouth-piece  is  closed  with  a  small  cotton  plug.     The  internal  diameter  of  tTie  tube  is  seven  mm. 

c,  the  shorter  tube  is  bent  at  right  angles  and  terminates  just  below  the  stopper.  The  external 
end  of  this  tube  is  closed  with  a  cotton  plug  to  prevent  the  entrance  of  micro-organisms  from  this 
side  of  the  apparatus.     The  internal  diameter  of  this  tube  is  also  seven  mm. 

The  organisms  which  developed  in  these  cultures  were  all  of  the  same  character — a  small 
yellow  bacillus  which  is  quite  common  in  the  air  of  the  laboratory.  In  the  experiments  in  which 
gelatin  remained  sterile,  the  precaution  had  been  taken  to  sterilize  the  apparatus  with  dry  heat  for 
an  hour  previous  to  introducing  the  gelatin,  besides  the  subsequent  sterilization  of  the  culture 
medium  on  three  successive  days.  If,  after  standing  in  the  working  room  for  several  days,  it  was 
found  that  the  culture  medium  was  sterile,  the  expired  breath  was  then  conducted  through  the 
apparatus  and  the  culture  was  kept  under  observation  (for  the  time  specified  in  the  table)  at  the 
room  temperature.  The  nature  of  the  organisms  that  developed  in  the  first  two  experiments,  and 
the  absence  of  any  growth  in  the  others,  makes  it  probable  that  they  developed  from  spores  that 
survived  the  fractional  sterilization  of  the  culture  medium.  It  is  improbable  that  they  were  carried 
in  the  expired  breath. 

Several  attempts  were  made  to  use  bouillon  and  litmus  milk  instead  of  gelatin,  as  the  culture 
medium.     Neither  of  the  former  media  was  found  to  be  suitable  for  the  purpose. 

Careful  examination  of  the  fluid  condensed  from  the  expired  air  was  made  with  high  powers, 
both  in  hanging  drops,  and  in  six  dried  and  stained  preparations,  but  nothing  resembling  bacteria  or 
epithelium  was  found.  A  few  amorphous  particles,  a  few  minute  apparently  crystalline  masses, 
and  here  and  there  a  fragment  resembling  vegetable  fibre,  were  all  that  could  be  seen. 

II. — A  series  of  experiments  was  made  to  determine  the  amount  of  ammonia,  of  albuminoid 
ammonia,  and  of  oxidizable  matters  contained  in  the  fluids  condensed  from  expired  air. 

The  apparatus  used  in  collecting  the  condensed  vapor  from  expired  breath  is  represented  in 
Fig.  2,  the  condenser  of  which  is  laid  in  ice.  Each  time  before  this  apparatus  was  brought  into 
use,  the  condenser  was  boiled  out  with  either  a  solution  of  bichromate  of  potash  and  sulphuric 
acid,  or  with  alkaline  permanganate  of  potash,  then  freely  rinsed  with  twice  distilled  water  until 
entirely  free  from  the  cleansing  solutions  used.  The  apparatus  was  then  quickly  connected 
together  and  placed  in  a  large  steam  sterilizer  for  an  hour.  The  condenser  was  then  packed  in 
ice  and  the  breath  exhaled  through  the  apparatus,  using  but  little  greater  expiratory  force  than  in 
ordinary  respiration.  In  several  of  the  experiments  a  gas  meter  was  attached  after  the  apparatus, 
in  order  to  measure  the  volume  of  air  exhaled.  This  was  found  to  approximate  a  third  of  a  cubic 
metre  per  hour,  during  which  time  as  much  as  12  c.  c.  of  inoisture  was  collected. 

The  amount  of  air  expired  in  ordinary  quiet  respiration  ranges  from  400  to  500  litres  per  hour. 
It  is  evident  that  the  diminished  amount  exhaled  in  the  experiment  did  not  represent  the  full 
respiratory  capacity  ;  the  reduction  observed  having  its  cause,  in  all  probability,  in  the  slightly 
greater  effort  required  to  conduct  the  expired  breath  through  the  apparatus.  It  was  noted  that  the 
number  of  expirations  ranged  from  twelve  to  fifteen   per  minute,  the  ordinary  rate  being  about 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


35 


eighteen  per  minute.     Tliis  was  also  caused  by  the  slight  obstruction  to  the  respiratory  current 
prolonging  the  expiratory  movettient.     Inhalation  took  place  through  the  nose. 


DESCRIPTION    OF    FIGURE    2. 

This  apparatus  was  used  to  condense  moisture  from  the  expired  breath.  It  consists  of  a  glass 
mouth-piece,  a,  having  an  internal  diameter  of  seven  millimetres  ;  its  length  being  twenty  centime- 
tres. The  distal  end  of  this  tube  is  bent  at  an  obtuse  angle  and  is  connected  with  a  glass  tube  of 
similar  size,  bent  at  right  angles,  and  inserted  through  one  of  the  openings  of  the  rubber  stopper 
of  the  wide-mouthed  flask  b.  The  other  opening  of  this  stopper  carries  a  similar  glass  tube,  also 
bent  at  right  angles,  attached  to  the  proximal  arm  of  the  condenser  c.  To  the  distal  arm  of  the 
condenser  is  attached  another  glass  tube,  also  bent  at  right  angles,  passing  through  one  of  the 
openings  of  the  rubber  stopper  of  the  wide-mouthed  tlask  e.  The  other  opening  in  this  stopper 
carries  a  glass  tube  of  similar  size,  also  bent  at  right  angles,  passing  nearly  to  the  bottom  of  the 
flask.  The  different  parts  of  the  apparatus  are  connected  together  by  means  of  short  pieces  of 
stout,  closely  fitting  rubber  tubing.  The  small  wide-mouthed  flask  b  serves  as  a  receptacle  for 
saliva.  The  tubing  in  the  stopper  closing  its  mouth  terminates  just  below  its  inner  surface.  The 
condenser  c  is  U-shaped,  with  each  of  its  arms  bent  at  right  angles  about  half-way  down  to  the 
lower  dilated  portion,  and  has  an  internal  diameter  of  seven  millimetres.  The  dilated  portion  of 
the  condenser  is  twelve  centimetres  in  length  and  four  centimetres  in  its  external  diameter.  The 
small  wide-mouthed  flask  e  is  nearly  filled  with  small,  pea-sized  pieces  of  pumice-stone  saturated 
with  concentrated  sulphuric  acid.  This  serves  to  arrest  the  organic  matter  in  any  air  that  might 
accidentally  enter  from  this  side  of  the  apparatus.  The  U-shaped  condenser  rests  in  a  square 
glass  dish  d,  20  x  8  x  8  centimetres  in  its  external  dimensions,  containing  cracked  ice. 


Fig.  2. — Apparatus  to  condense  moisture  from  the  expired  breath. 

In  order  to  adapt  the  mouth-piece  of  this  apparatus  to  the  fistulous  opening  in  the  throat  of 
the  man  that  had  had  his  larynx  removed,  the  proximal  end  of  the  mouth-piece  was  attached  to  a 
porcelain  mouth-piece  used  for  speaking-tubes.  This  was  padded  with  several  layers  of  cheese 
cloth,  and  the  loose  end  of  this  lied  around  his  neck  to  hold  it  in  position.  In  this  manner  he  was 
able  to  exhale  through  the  apparatus  without  any  difficulty. 

Some  of  the  condensed  fluid  was  collected  from  my  own  breath  and  that  of  other  healthy 
persons  ;  other  portions  were  collected  from  a  man  having  a  permanent  fistulous  opening  in  his 
throat  through  which  he  breatlied  ;  there  being  no  connection  whatever  with  the  mouth  and  upper 
air  passages.  Some  fluid  was  also  collected  from  the  breath  of  a  man  suffering  from  advanced 
tuberculaT  disease  of  the  lungs. 

The  amount  of  free  and  albuminoid  ammonia  in  this  condensed  fluid,  as  estimated  according 
to  the  well-known  method  of  Wanklyn,  Chapman,  and  Smith,  is  shown  in  Table  B,  together  with 
the  amount  of  fluid  used  in  each  of  these  determinations  and  the  time  required  to  collect  these 
portions  of  fluid.    A  definite  portion  of  the  fluid  was  diluted  with  500  c.  c.  of  twice  distilled  water, 


36 


THE  COMPOSITION  OF  EXPIRED  AIR, 


and  the  ammonia  in  a  like  quantity  of  the  same  water  was  determined  simultaneously  and 
deducted  from  the  amount  found  in  the  diluted  fluid.  The  minute  quantities  of  ammonia  found 
in  the  fluid  in  some  of  these  determinations  required  the  greatest  care  in  manipulation  to  avoid  all 
sources  of  contamination — in  the  collection  of  the  fluid  as  well  as  subsequently  in  the  distillation 
and  nesslerization.  Tlie  greatest  care  had  to  be  exercised,  therefore,  in  cleansing  all  ajiparatus 
used,  and  in  the  preparation  of  the  different  reagents. 

The  fluid  for  the  first  seven  determinations  was  collected  from  my  own  breath,  and,  for  the 
next  thirteen  determinations,  from  the  breath  of  the  man  with  the  tracheal  fistula.  The  remainder 
of  the  determinations  were  made  on  the  fluids  collected  from  the  breath  of  the  consumptive. 

Table  B. 

determination  of  free  and  albuminoid  ammonia  in  condensed  fluid  of  respiration. 


Grams  per 

lire  of  fluid. 

Time  and  amt.  collected. 

No. 

Amount  of 
fluid  used. 

Date. 

Remarks. 

Free  NH3. 

Alb.  NHs. 

Minutes. 

c.  c.  of  fluid. 

1893. 

I 

5  c.  c. 

.0198 

.005 

60 

10 

Dec.  IS 

My  own  breath. 

2 

S 

.031 

.004 

ss 

10 

"     20 

3 

S     " 

.0314 

.0038 

it        it         t( 

4 

S     " 

.0026 

.0162 

60 

12 

"     28 

((            U             a 

5 

5     " 

.0028 

.016 

1894. 

a          n           a 

6 

4    " 

•0245 

.004 

55 

8.S 

Jan.     I 

u           n 

7 

4     " 

.022 

Defective. 

8 

5     " 

.0004 

.0002 

"     16 

Mr.  Rickey's  breath. 

9 

5     " 

.0006 

.0002 

(Tracheal  fistula.) 

10 

5     " 

.0003 

.0002 

"     19 

(f                 a 

1 1 

5 

.0003 

.0002 

12 

5     ' 

.0004 

.0006 

"     22 

13 

5     " 

*  Failure. 

*  Failure. 

a                  (( 

14 

5 

.0005 

.0005 

"     25 

i< 

15 

5     " 

.0006 

.0006 

(<                  i( 

16 

5     " 

.0004 

.0005 

"     26 

((                 a 

17 

5     ' 

.0004 

.0005 

18 

10 

.0007 

.0005 

r,  '9 

" 

19 

10    " 

.0006 

.0002 

"  30 

u                           t( 

20 

21-5" 

.0003 

.OOOI 

Feb.     I 
1895- 

f(                (( 

21 

IS     " 

.005S 

.0003 

6S 

15 

Jan.    18 

Consumptive  person. 

22 

12     " 

.0034 

.0005 

60 

12.5 

Feb.    7 

a                        li 

23 

IS     " 

.0023 

•o°33 

120 

20 

"     13 

((                        li 

24 

10    " 

.0005 

.009s 

120 

16 

"     19 

a                          a 

The  amount  of  organic  matters  present  in  the  condensed  fluid,  as  shown  by  its  reducing  power 
upon  solution  of  permanganate  of  potash,  is  represented  in  Table  C,  the  results  being  calculated 
to  Mg.  of  O.  consumed  to  one  litre  of  the  condensed  fluid.  The  table  also  shows  the  amount  of 
fluid  used  in  each  of  the  determinations  and  the  time  required  to  collect  such  amount.  In  three 
of  the  experiments  the  amount  of  air  expired  is  also  given.  These  determinations  were  made 
according  to  the  methods  now  in  common  use  for  the  determination  of  organic  matter  in  water  as 
modified  by  Kubel  ;  the  fluid  being  diluted  with  a  definite  amount  of  distilled  water,  the  reducing 
power  on  permanganate  of  which  was  simultaneously  determined  and  deduced  from  the  results 
obtained.     The  ebullition  of  the  fluid  was  always  carefully  timed — the  time  being  five  minutes. 

*  Merely  a  trace  found. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 

Table  C. 

determination  of  oxidizable  matter  in  condensed  moisture  of  respiration. 


37 


Time  and  amount 

:ollected. 

Mgm.  of  Amount 

No. 

Date. 

Amount 
used c.c. 

0.  con- 
sumed to 

of  air 
expired. 

Remarks. 

Hours. 

c.c.  of 
fluid. 

I  litre. 

Litres. 

1894. 

1 

Jan. 

3' 

I 

35 

3.5  '    8°i 

I).  Tlickey's  breath  (tracheal  fistula). 

2 

it 

31 

I 

4 

4         TI.68 

(i              .(            It 

3 

(( 

3' 

1 

3 

3          9345S 

It                tt              tt            tt 

4 

4< 

31 

I 

'•5 

1.5  1  24.916 

tt                tt              tt            It 

5 

Sept. 

6 

3 

35 

25 

12.04 

982.5 

My  own  breath. 

6 

** 

12 

I 

12 

10 

8.89 

333-3 

tt      tt        It 

7 

(( 

17 

35 

min. 

8 

8 

11.25 

176 

Dr.  Gillespie's  breath. 

'895- 

8 

Jan. 

26 

7-5 

7 

6.86 

Consumptive's      " 

9 

it 

29 

20 

(t 

4  75 

4-75!  1830 

Four  hours  after  last  meal.* 

lO 

(( 

29 

20 

tt 

4-25 

4.25     2.27 

Half  hour      "        "       " 

II 

it 

30 

15 

i( 

4 

4       Failure. 

Three  and  a  half  hours  after  last  meal. 

12 

it 

3° 

15 

tt 

4 

4       Failure. 

Half  hour  after  last  meal. 

13 

(< 

3> 

16 

16      i  19.32 

Consumptive's  breath. 

«4 

n 

3" 

'5 

tt 

3-75 

3-75  '0-40 

Four  hours  after  last  meal. 

IS 

tt 

31 

15 

tt 

3-75 

3-75     2.60 

Half  hour       "        "       " 

i6 

Feb. 

I 

15 

i( 

4-5 

4-5       757 

Three  and  a  half  hours  after  last  meal. 

17 

** 

I 

10 

ti 

3 

3         8-1° 

Half  hour  after  last  meal. 

i8 

If 

2 

15 

tt 

3-8 

3.8     10.105 

Three  hours  "      "       " 

'9 

U 

2 

»5 

i( 

3-5 

3-5     15485 

Half  hour      "      "       " 

20 

<( 

2 

60 

'* 

9-75 

9-75     7-5° 

Consumptive's  breath. 

21 

(< 

4 

15 

tt 

4 

4 

10.90 

Four  hours  after  last  meal. 

22 

a 

4 

'5 

<t 

4 

4 

9.70 

Four  and  a  half  hours  after  last  meal, 
septic  mouth  wash. 

anti- 

«3 

(( 

6 

15 

tt 

38 

3-8 

12.76 

Four  and  a  half  hours  after  last  meal. 

24 

« 

•9 

120 

tt 

16 

5 

19.12 

Consumptive's  breath. 

25 

<< 

28 

'5 

it 

3-75 

3-75 

Failure. 

One  and  a  half  hours  after  meal. 

26 

it 

28    60 

(t 

6.25 

6.25 

33-90 

Consumptive's  breath. 

27 

" 

28    10 

*' 

3-5 

325 

8.83 

Three  and  a  half  hours  after  meal. 

28 

" 

28 

10 

2.75 

2.75 

347 

Four  hours  after  meal,   mouth   rinsed 
warm  water. 

with 

29 

Mch. 

I 

10 

<i 

2.50 

2.50 

756 

Four  hours  after  meal. 

30 

" 

I 

10 

tt 

2.75 

2-75 

3-47 

Half  hour       " 

31 

It 

2 

15 

It 

3-75 

3-75 

2.62 

Three  hours  " 

32 

tt 

2      15 

*' 

3  25 

3-25 

"•515 

Three  and  a  half  hours  after  meal,  mouth 

rinsed  with  warm  water. 

33 

tt 

2 

15 

tt 

4 

4 

1.23 

Half  hour  after  last  meal. 

The  fluids  for  these  determinations  were  collected  from  the  breath  of  the  man  with  the  tra- 
cheal fistula  ;  from  the  breath  of  the  consumptive  ;  and  from  my  own  breath  and  that  of  another 
healthy  person.  With  the  exception  of  one  of  the  results  obtained  with  fluid  collected  from  the 
breath  of  the  man  with  the  tracheal  fistula,  which  result  is  out  of  accord  with  the  others  (cause 
unknown),  tlie  determinations  show  no  marked  variation  in  the  amount  of  oxidizable  matter,  what- 
ever the  source  of  the  fluid  or  conditions  of  the  person  from  whose  breath  it  was  collected,  though 
only  a  few  experiments  were  made.     Just  before  collecting  the  fluid  for  several  of  the  later  dcter- 


*  The  Buids  for  the  determinations  before  and  after  meals  were  collected  from  my  own  breath. 


38 


THE  COMPOSITION  OF  EXPIRED  AIR, 


minations  in  the  table,  tlic  moiitli  was  well  rinsed  in  a  weak  solution  of  formalin  or  with  warm  water. 
A  reduction  of  1.2  Mg.  of  O.  per  litre  in  the  23d  from  the  amount  required  for  the  fluid  collected 
the  half  an  hour  before,  seems  to  have  resulted  from  the  use  of  the  antiseptic  mouth  wash,  in  others  a 
still  greater  reduction  was  brought  about  by  simply  rinsing  the  mouth  several  times  with  warm  water. 
Several  efforts  were  made  to  obtain  evidence  as  to  the  chemical  nature  of  the  condensed  fluid 
collected  from  my  own  breath.  Eiglity  (80)  litres  of  expired  air  were  conducted  through  50  c.  c.  of 
a  one  per  cent,  solution  of  oxalic  acid  in  ten  minutes.  This  fluid  gave  a  decided  yellowish-brown 
color  w'ith  i.  c.  c.  of  Nessler's  reagent,  showing  at  least  five  times  as  much  ammonia  as  was  present 
in  the  distilled  water  used  to  make  the  oxalic  acid  solution.  'I'lie  fluid  condensed  from  exhaled 
breath,  obtained  by  conducting  the  breath  through  a  condensing  apparatus  laid  in  ice,  was  tested 
with  the  following  reagents  for  the  presence  of  a  volatile  organic  alkaloid  :  AUCI3,  PtCI^, 
Amnion.  Molybdate,  Ag  NO3  ;  reaction  negative.  Nessler's  reagent  ])roduced  a  yellow  color,  and 
a  few  drops  of  a  10  per  cent,  solution  of  HgCU  with  a  few  drops  of  a  10  per  cent,  solution  of 
KI  also  gave  a  yellow  color. 

The  results  of  the  tests,  though  few  in  number,  give  no  evidence  of  the  presence  of  exi)ira- 
tory  products  other  than  those  indicated  by  the  determinations  of  ammonia,  and  the  reducing 
power  on  solution  of  permanganate  of  potash. 

III. — Experiments  with  fluid  condensed  from  the  air  of  a  large  surgical  ward  in  the  University 

Hospital,  with  and  without  filtration  of  the  air. 

Several  efforts  were  made  to  collect  moisture  from  the 
air  of  a  crowded  surgical  ward  of  the  Hospital  by  means  of 
a  large  glass  funnel,  sealed  at  the  neck  and  filled  with  ice. 
A  small  beaker  was  placed  beneath  the  funnel  to  collect 
any  moisture  condensing  on  its  exterior.  This  method 
proved  unsuccessful,  and  was  abandoned.  An  apparatus, 
shown  in  Fig.  3,  and  arranged  as  shown  in  Fig.  4,  was 
placed  on  a  mantel  over  an  unused  open  fire-place  at  one 
end  of  the  ward. 

Description  of  the  apparatus  used  to  condense  the 
moisture  in  the  air  of  the  hospital  ward  : 

Fig.  3  represents  the  condenser,  consisting  of  a,  a  small 
glass  receptacle  eleven  centimetres  in  height  and  three 
centimetres  in  diameter  at  its  widest  part,  and  having  a 
capacity  of  50  c.  c.  This  receptacle  has  two  ojienings,  the 
one"  at  the  top  being  closed  with  a  closely  fitting,  hollow, 
glass  stopper  ;  the  second  opening  consists  of  a  glass  tube 
coming  obliquely  from  the  expanded  portion  near  the  top, 
and  at  a  distance  of  three  centimetres  bends  upward  along 
the  side  of  the  receptacle.  This  serves  as  the  exit  tube  to 
the  receptacle,  while  the  air  enters  through  the  hollow  glass 
stopper  closing  the  other  opening.  Each  of  the  tubes  has  an  internal  diameter  of  four  millimetres.  The 
spiral  portion  of  the  condenser  consists  of  a  piece  of  block- tin  tubing,  b,  three  metres  in  length, 
and  five  millimetres  in  internal  diameter.  This  is  connected  with  the  entrance  tube  of  the  recep- 
tacle by  means  of  a  short  piece  of  rubber  tubing,  and  with  the  dust  filter  by  a  longer  piece  of 
rubber  tubing.  The  exit  tube  of  the  receptacle  has  a  ]iiece  of  glass  tubing,  thirty  centimetres  in 
length,  and  five  centimetres  in  internal  diameter,  fused  to  its  end.  This  is  bent  at  right  angles 
near  its  upper  extremity,  and  connected  with  the  gas  meter  by  means  of  a  piece  of  rubber  tubing. 

Fig.  4,  represents  the  apparatus  as  arranged  in  the  hospital  ward,     a  represents  an  inverted 

bell-jar  with  the  condenser  packed  in  ice.     The  bell-jar  is  su]jported  by  an  iron  tripod,  d.     The 

dust   filter,   consisting   of    a    glass   tube    loosely   packed   with    asbestos,   is   represented    at  c,  and 

is  attached  to  a   stative  by  means  of  a  clamp,  while  e  represents  the  gas  meter,  and  /  the  water 

•  faucet  in  the  lavatory.     The  meter  is  connected  with  the  faucet  by  means  of  a  long  piece  of  block- 


Fic 


3. — Coinleuiier  of  ajjparalus  sliown 
in  Fig.  4.     (X  5-) 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


39 


tin  tubing  of  i|  centimetres  internal  diameter.  ^"^  represents  the  Chapman  water  pump  attached 
to  the  faucet. 

The  dust  filter,  c,  is  twenty  centimetres  in  length,  consisting  of  a  narrow  portion  four  centi- 
metres long  and  three  millimetres  in  internal  diameter,  and  of  a  wider  portion  sixteen  centimetres 
long  and  twelve  millimetres  in  internal  diameter. 

The  condenser  was  cleansed  by  rinsing  it  with  a  solution  of  bichromate  of  potash  and  sulphuric 
acid,  then  removing  all  trace  of  this  solution  by  rinsing  it  repeatedly  with  twice  distilled  water. 
The  cleansing  of  the  apparatus  was  greatly  facilitated  by  attaching  it  to  a  Chapman  water  pump  in 
the  laboratory,  and  drawing  the  cleansing  solution  and  distilled  water  through  it  in  large  quantities. 
It  was  then  placed  in  the  inverted  bell  jar,  (jacked  in  ice,  and  connected  with  the  meter  and  pump 
in  the  hospital  ward. 


l^=>^i 

^^^^=iii^ 

© 

=ca=d 

,  c  ^_ 

h 

^ffi 

-M 

Q^^ 

L Hi 

d 

Fig.  4. — Apparatus  used  to  condense  moisture  from  the  air  of  llie  Hospital  Ward. 

With  this  apparatus  a  small  amount  of  fluid  was  collected  on  days  when  the  atmosphere  was 
saturated  with  moisture,  but  if  this  fluid  was  allowed  to  remain  in  the  receptacle  during  several  days 
of  clear  weather  it  slowly  evaporated.  However,  enough  fluid  was  collected  in  this  manner  to 
make  several  determinations  of  the  free  and  albuminoid  ammonia  in  it.  The  results  thus  obtained 
are  shown  in  Table  1)  ;  the  first  and  third  experiments  showing  results  obtained  without  placing  a 
dust  filter  of  asbestos  before  the  condenser.  The  second  and  fourth  experiments  show  the  results 
obtained  by  attaching  such  a  dust  filter. 

T.vulf.  D. 

determination  of  free  and  albuminoid  ammonia  in  the  moisture  condensed  from  the 

air  of  the  hospital  ward. 


No. 

Date. 

Time. 

Litres  of  air 

Amt.  of  moisture 

Grms.  per  loco  cbm.  air. 

No.  of 
bacteria  per 
c.  c.  of  fluid. 

Remarks. 

aspirated. 

condensed. 

Free  NHj. 

Alb.  NHj. 

I 

2 
3 

4 

1894 

Dec.  13 

1895 
Jan.    9 

"    18 
Mch.  4 

Hours. 
43^ 

4ii 
34i- 
33 

4612.9 

39903 
1669.7 
1980.0 

3.  c.c. 

7.  " 

3-      " 
2.6    " 

0.0210 

0.00075 

0.0012 

0.0015 

0.0028 

0.00125 

0.0015 

O.OOIO 

3'4° 
1331 

No  dust  filter. 

Dust  filter. 
No  dust  filter. 
Dust  filter. 

Microscopic  examination  of  the  fluid  condensed  from  the  air  of  the  hospital  ward  showed  :  a 
number  of  small  amorphous  particles — black,  yellow,  and  colorless  ;  a  few  small  crystals,  a  few 
epithelial  scales,  small  bits  of  vegetable  fibre,  and  a  few  bacteria. 

Cultures  made  from  this  fluid  showed  numerous  colonies  of  moulds,  numerous  common  air  and 
water  organisms,  some  of  which  rapidly  liquefied  the  gelatin  of  the  cultures.  B.  pyocyanus  was 
found  in  one  instance,  in  others  a  yellow  sarcina,  and  yeasts  of  different  colors.       Besides  these  a 


40 


THE  COMPOSITION  OF  EXPIRED  AIR, 


bacillus  belonging,  apparently,  to  the  B.  coli  group  was  found  in  most  of  the  cultures  ;  in  one 
instance  this  bacillus  was  present  in  very  large  numbers  and  excluded  nearly  all  the  other  forms. 
It  was  also  noted  in  the  gelatin  plates  exposed  in  the  ward,  and  in  the  ctdtures  from  dust  collected 
near  the  ajiparatus. 

On  several  occasions  the  dust  which  had  collected  on  the  meter  and  mantel  during  the  night 
was  taken  up  on  a  sterilized  cotton  swab  and  inoculated  upon  gelatin  plates.  The  cultures  in 
these  plates  did  not  differ  greatly  from  those  made  from  the  fluid,  except  that  the  moulds  were 
present  in  larger  proportion  than  the  other  organisms  noted  in  the  cultures  from  the  fluid. 

Gelatin  plates  exposed  to  the  air  of  the  ward  showed  the  same  character  of  organisms  as  in  the 
cultures  from  the  condensed  fluid  and  those  which  developed  from  the  dust  collected  in  the  vicinity 
of  the  apparatus.  In  addition  to  the  species  already  noted,  colonies  of  staphylococcus  aureus 
and  albus  were  also  noted  in  these  plates. 

The  small  amount  of  fluid  collected  from  the  air  of  the  hospital  ward  in  the  manner  stated, 
and  the  rapidity  with  which  it  evaporated  on  clear  days,  made  it  impossible  to  collect  a  sufficient 
quantity  to  inoculate  it  into  animals.  To  overcome  this  difficulty  a  small  quantity  of  sterilized 
glycerine  (7.5  to  10  c.  c.)  was  aspirated  through  the  condensers  after  it  had  been  cleansed.  It  is 
doubtful,  however,  whether  this  served  to  withdraw  an  appreciable  amount  of  moisture  from  the  air. 
After  aspirating  air  through  the  apparatus  for  several  days  it  was  brought  to  the  laboratory  and  the 
fluid  in  the  receptacle  transferred  to  a  small  sterilized  flask.  The  condenser  was  then  washed  out 
by  aspirating  8  to  10  c.  c.  of  twice  distilled  water  (sterilized)  through  it.  This  was  added  to  the 
fluid  poured  from  the  receptacle,  thoroughly  mixed  with  it,  and  inoculated  into  animals.  The 
glycerine  in  this  fluid  inoculated  into  the  animals  was  diluted  at  least  50  per  cent.  Three  sets  of 
animals  were  inoculated  and  each  time  a  control  animal  was  inoculated  with  equal  parts  of  glycerine 
and  distilled  water  that  had  been  sterilized  for  one  hour.  The  results  of  these  experiments  are 
shown  in  Table  E. 

Table  E. 

collection  of  bacteria,  etc.,  from  the  atmosphere  of  the  hospital  ward,  using  glycerine 

in  the  absorption  apparatus. 


No. 

D.ite 

Time. 

1894. 

Hours. 

I 

Dec.    5 

47^ 

2 

"     II 

1895. 

69I 

3 

Jan.  I 

47i 

4 

"      3 

44f 

5 

"     S 

S^h 

Litres  of  air 
Aspirated. 


i333«.8 


7754-2 
7669.3 
4924.2 


Amt.  of 

glycerine 

used. 

Weight  of  rabbit  and  amt.  of  fluid  injected. 

Weight. 

c.  c. 

Weight. 

c.  c. 

Weight, 
(control 
animal.) 

c.c. 

Grams. 

Grams. 

Grams. 

10  c.  c. 

10  "  ' 

7.5" 

If 

3°5° 
2205 
1970 

6 
6 
6 

1 130 

2350 
1280 

2 
6 
6 

1025 
2205 
1400 

2 
6 
6 

No.  of  bacteria 

in  dilute  fluid, 

per  c.  c. 


900 

45° 

267s 

1893 
1646 


The  animals  inoculated  with  the  products  collected  from  the  air  of  the  hospital  ward  in  the 
manner  stated  were  under  observation  for  two  months.  Three  of  these  animals  died  during  the 
time  they  were  under  observation.  The  control  animal  of  the  third  series  died  after  twelve  days. 
This  animal  was  observed  to  be  in]  poor  health  for  several  days  before  its  death.  On  examination, 
Jwsi  mortem,  it  was  found  to  have  had  a  good-sized  abscess  in  the  right  axillary  fossa,  which  had 
ruptured  externally  :  The  liver  presented  numerous  whitish  bands  and  foci  on  all  of  its  surfaces 
and  throughout  the  matrix.  .\  number  of  echinococcus  cysts  were  found  adherent  to  the  liver, 
spleen,  and  the  omentum.  The  kidneys  were  normal  in  size  and  appearance,  and  the  capsule  was 
easily  removed.     The  other  organs  appeared  normal. 

Cultures  v/ere  taken  from  the  abscess,  blood,  lungs,  liver,  spleen,  and  kidneys.  Those  from  the 
site  of  the  abscess  were  the  only  ones  developing  any  growth.  The  prevailing  organisms  in  the 
cultures  from  the  abscess  were  staphylococcus  albus  and  aureus. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  41 

Cover-slip  preparations  were  made  from  the  abscess,  blood,  lungs,  liver,  spleen,  and  kidney. 
Those  from  the  site  of  the  abscess  were  the  only  ones  showing  any  organisms  ;  nimierous  cocci, 
with  a  few  bacilli,  were  observed. 

Microscopic  examination  of  the  organs  hardened  in  alcohol  and  mounted  in  celloidin  :  The 
liver  presented  some  increase  of  connective-tissue  elements  between  the  lobules.  The  whitish 
bands  on  the  surface  of  the  organ,  noted  at  the  autopsy,  were  found  to  be  due  to  this  increase  in 
connective-tissue  elements  in  the  inter-lobular  spaces.  No  change  was  noticed  in  tlie  liver  cells 
themselves.     All  the  other  organs  were  found  to  be  normal. 

The  nature  of  the  substances  inoculated  into  this  control  animal  (6  c.  c.  of  equal  parts  of  steril- 
ized glycerine  and  distilled  water)  and  the  antiseptic  precautions  observed  in  the  inoculation  make 
it  doubtful  whether  the  source  of  infection  is  traceable  to  the  e-xperiment.  The  changes  noted  in 
the  liver  are  of  such  a  nature  as  to  indicate  their  production  by  causes  preceding  even  those  which 
brought  about  the  death  of  the  animal. 

Rabbit  No.  2  of  the  first  series,  having  received  2  c.  c.  of  the  fluid  obtained  by  aspirating  the 
air  of  the  hospital  ward  through  the  condensing  apparatus  moistened  with  sterilized  glycerine, 
died  after  35  days.  Autopsy:  Half-grown  rabbit,  poorly  nourished,  and  adipose  all  used  up, 
presented  nothing  important  externally.  Internally  :  A  small  amount  of  clear  fluid  in  the  abdomi- 
nal cavity  ;  the  liver  is  somewhat  darker  than  normal,  mottled,  and  contains  a  few  psorosperms. 
Spleen  is  normal.  Kidneys  and  adrenals  are  normal  in  appearance.  The  right  lung  is  considerably 
congested,  being  readily  torn  ;  the  left  is  also  slightly  congested.  The  right  side  of  the  heart  is 
filled  with  dark  fluid  blood  ;  the  left  side  is  nearly  empty.  Several  echinococcus  cysts  were  found 
in  the  abdominal  cavity. 

Cover-slip  preparations  were  made  from  the  alidominal  fluid,  the  kidneys,  liver,  spleen,  lung, 
and  blood  ;  all  proved  negative. 

The  organs  were  preserved  in  alcohol  and  mounted  in  celloidin  for  microscopic  examination. 

Microscopic  examination  of  the  organs  :  Left  lung  showed  the  capillaries  and  larger  vessels 
very  much  dilated  and  filled  with  blood.  Infiltration  of  leucocytes  was  noted  here  and  there. 
Right  lung  showed  marked  proliferation  of  cells  and  infiltration  of  leucocytes.  Many  of  the  air 
cells  were  obliterated.     The  liver,  kidneys,  and  spleen  were  normal. 

Rabbit  No.  i  of  the  second  series,  inoculated  with  the  fluid  obtained  from  the  air  of  the  hospital 
ward,  died  after  38  days.  Autopsy  :  Full-grown  rabbit,  shows  numerous  bruises  and  lacerations  of 
the  skin  over  various  parts  of  the  body.  Many  of  the  wounds  along  the  sides  and  back  show 
ecchymoses  under  the  skin.  .Adipose  not  all  used  up.  Internally  :  Liver  slightly  darker  and  some- 
what larger,  apparently,  than  normal.  Spleen  is  larger  than  normal.  Kidneys  embedded  in  fat, 
normal  in  appearance.     Lungs  and  heart  normal.     Blood  is  dark  and  fluid. 

Cover-slips  were  made  from  all  the  organs  with  negative  results. 

The  organs  were  preserved  in  alcohol  and  mounted  in  celloidin  for  microscopic  examination. 

Microscopic  examination  of  the  organs  :  No  abnormalities  could  be  found  in  any  of  the  organs  ; 
all  appearing  to  be  normal. 

The  remaining  rabbits  of  these  series  showed  no  symptoms  of  any  deleterious  influence  from 
the  fluid  inoculated.     No  swelling  or  formation  of  abscess  was  noted  in  any  of  them. 

Rabbit  No.  2  of  the  first  series  evidently  died  of  lung  disease,  as  shown  aX post  mortem.  As  to 
the  causation  of  this  disease,  it  is  impossible  to  venture  an  opinion.  Rabbit  No.  i  of  the  second 
series  died  of  causes  which  left  apparently  no  manifestations  pointing  to  their  nature.*  Rabbit  No. 
3  (control)  of  the  third  series  evidently  died  from  the  effects  of  the  extensive  axillary  abscess.  As  to 
the  source  of  the  infection,  no  decided  opinion  can  be  given.  Probably  the  infection  gained  an 
entrance  through  the  inoculation  wound. 

Some  experiments  were  made  to  determine  the  amount  of  oxidizable  inatter  in  atmospheric  air. 
At  first  a  measured  amount  of  air  was  slowly  aspirated  through  twice  distilled  water,  and  the  amount 
of  oxidizable  matter  extracted  from  the  air  estimated  according  to  the  method  used  for  determin- 

•Dcith  may  have  resulted  from  injury,  as  shown  by  the  contusions  and  wounds  noted  at  autopsy.  These  wounds 
were  probably  inflicted  by  other  rjbbits  in  the  same  cage. 


42 


THE  COMPOSITION  OF  EXPIRED  AIR, 


ing  the  oxidizable  matters  in  the  condensed  Ihiid  of  respiration.  In  the  later  experiments  the  air 
was  conducted  through  two  flasks — the  first  containing  loo  c.  c.  of  a  i  per  cent,  solution  of  sulphuric 
acid,  the  second  loo  c.  c.  of  a  i  per  cent,  solution  of  potassium  hydroxide.  After  aspirating  a 
jneasured  amount  of  air  through  these  solutions,  50  c.  c.  of  each  were  mixed  together  and  the 
amount  of  oxidizable  matter  determined  as  in  the  earlier  experiments.  The  results  are  shown  in 
Table  F. 

Tadi-e  F. 

determinations  of  oxidizable  organic  matters  in  atmospheric  air. 


No. 

Absorbent  used. 

Amount 
used  c.  c. 

Litres  of  air 
aspirated. 

Time  of 
aspiration. 

0.  consumed 

to  1000  b.  ni. 

of  air. 

Date. 

Kemarl<s 

Hours. 

Grms. 

1894 

I 

Distilled  H^O. 

125 

200 

20 

•340 

Aug.  20 

Laboratory 

air. 

2 

150 

240 

22 

*Failure 

"      21 

i( 

*' 

3 

((                       It 

15° 

240 

20 

.121 

"      22 

i( 

(( 

4 

.(                   it 

15° 

240 

20 

.058 

"      23 

t( 

11 

5 

11                  ii 

15° 

240 

20 

Failure 

"      24 

t( 

i( 

6 

f(                       n 

15° 

240 

20 

Failure 

"      25 

<t 

t( 

7 

a                 li 

150 

240 

20 

Failure 

"      26 

a 

n 

8 

n                 n 

^5° 

300 

20 

.030 

"      27 

" 

t( 

9 

it                  a 

15° 

320 

20 

•°S9 

'.',      ^9 

*' 

tl 

10 

i(                 a 

'5° 

280 

20 

.085 

"      3° 

ti 

" 

n 

((                 (( 

>S° 

369 

20A 

.013 

Sept.  6 

(1 

(1 

12 

it                 (( 

100 

900 

5° 

.204 

"       8 

it 

ii 

13 

((                 11 

ISO 

360 

24 

Failure 

"     n 

i( 

it 

14 

a                  a 

iS° 

360 

20 

Failure 

"     12 

(( 

11 

IS 

j  if,  solution  HoSOi 
(  ifo       "          K  H  0 

100 
100 

1000 

22 

■558 

"     18 

External 

(( 

16 

t(                             (( 

100 
100 

911.25 

20 

.086 

Oct.  2 

(( 

11 

17 

(I                             11 

100 

TOO 

690.5 

20 

.068 

"     3 

It 

il 

18 

1<                             (( 

100 
100 

433 

20 

.062 

"     4 

" 

tt 

11                  a 

100 

"     6 

li 

n 

19 

100 

447 

22 

.007 

Theseexperiments  were  made  at  a  season  of  the  year  when  the  windows  of  the  laboratory  were 
open  most  of  the  time  and  the  amount  of  dust  floating  in  the  laboratory  air  must  have  been  about 
equal  to  that  in  the  external  air.  The  method  em|)loyed  to  obtain  the  oxidizable  matter  from  the 
external  air  is  preferable  to  that  employed  for  the  laboratory  air,  and,  since  equal  portions  of  the 
solutions  used  neutralize  each  other,  they  have  no  objectionable  influence  upon  the  process  of 
determination  of  the  oxidizable  matter. 

In  several  instances  a  portion  of  the  water,  containing  the  oxidizable  matter  extracted  from  the 
air,  was  treated  with  AgNOj,  HgCU,  AuCl.,,  PtCl^,  K^FeCyc,  K^FejCyia,  KHO,  Ba(H0)2, 
HjS04,  I,  and  with  phosphomolybdic  acid,  am.  molybdate,  but  no  reaction  was  obtained  with  any 
of  these,  either  in  hot  or  cold  solution.  Nessler's  reagent  gave  a  deep  yellow  color,  and  HgCU  with 
KI  produced  a  lemon-colored  precipitate,  rapidly  changing  to  red,  with  deposit  of  HgU. 

IV. — Experiments  on  mice  and  birds  confined  in  glass  jars,  by  the  method  used  by 
Hammond  (10). 

The  exact  conditions  under  which  Hammond  conducted  his  experiment  are  not  given  in  his 
treatise,  and  the  size  of  the  jar  he  used  is  uncertain.  Taking  the  relative  sizes  of  the  animal,  jar, 
and  the  other  parts  of  the  apparatus  shown  in  the  accompanying  figure,  it  seems  probable  that  he 
used  a  jar  of  at  least  four  litres'  capacity.     In  the  apparatus  used  for  our  experiments,  two-  and  four- 

*By  "Failure"  is  meant  that  merely  a  trace  of  organic  matter  was  found. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


43 


litre  jars  were  used.  'I'lie  arrangements  for  the  absorption  of  moisture,  COj,  and  for  the  intro- 
duction of  fresh  air,  were  the  exact  counterparts  of  these  arrangements  in  Hammond's  apparatus, 
judging  from  his  description  and  engraving.  Fresh  air  was  supplied  at  intervals  of  one-half  to  one 
hour.  This  was  accomplished  by  attaching  a  graduated  aspirator  to  the  Geissler  potash  bulbs 
containing  the  Ba(HO)o  solution. 

Tiie  results  obtained  in  these  experi- 
ments are  shown  in  Table  G.  Hammond 
claims  that  in  his  experiments  a  mouse  in- 
variably died  within  one  hour.  In  our  ex- 
periments all  the  animals  lived  over  three 
hours,  and  some  even  longer  than  six  hours. 
The  great  difference  in  the  duration  of  life 
for  different  animals  may  be  accounted  for 
in  the  varying  susceptibility  of  different 
animals  of  the  same  species  to  the  almos- 
l)hcric  conditions  in  the  jar,  but  the  still 
greater  difference  in  the  duration  of  life  in 

our  experiments,  as  compared   with  Ham- 

j.  1.  ^1  »^  -L    ^    J    ^  ¥lG.  5.  —  Hammond's  apparatus. 

mond  s   results,   cannot    be   attributed   to  ^^ 

the  same  cause,  and,  since  it  is  not  known  positively  what  the  ca])acity  of  the  jars  was  which  he 

used  it  would  be  useless  to  speculate  on  the  point. 

Fig.  5  shows  Hammond's  apparatus  as  given  in  his  treatise  (Fig.  lo,  p.  170),  and  is  an  accurate 
representation  of  the  apparatus  used  by  us,  except  that  it  does  not  show  the  graduated  aspirator 
connected  wuth  the  free  end  of  the  Geissler  potash  bulbs,  by  means  of  which  a  known  amount  of 
fresh  air  was  introduced  at  stated  intervals  during  the  experiment. 


Table  G. 
the  "  hammond  experiment.' 


K.\am. 

of  air. 

Date. 

Capacity  of 
the  jar. 

Amt.  of  air 
aspirated. 

Time. 

Aniii.al. 

Weight. 

Remarks. 

CO.. 

0. 

1893- 

H'rs. 

Grms. 

^ 

^ 

I 

Dec.  IS 

4000  c.  c. 

250  C.  C. 

.S 

Sparrow. 

20 

Alive 

;   revived. 

2 

"      16 

185  '' 

s+ 

20 

ii 

(( 

3 

"      18 

((       t( 

600     " 

6 

Mouse. 

14 

tt 

(( 

4 

"      19 

it       (( 

600     " 

6 

u 

15 

It 

tt 

5 

"      20 

2000    " 

300    " 

6 

t( 

f4 

tt 

tt 

6 

"      20 

300    " 

6 

tt 

15 

1 

7 

"      21 

4000        *' 

225    " 

■S 

Sparrow. 

26 

"    ( 

-  Same  animal. 

8 

"     22 
1894. 

225   " 

s 

26 

" 

9 

Feb.     9 

300    " 

3 

tt 

Died. 

10 

;;    9 

u         u 

35°     " 

4 

II 

"   10 

400     " 

3i- 

tt 

It 

12 

"         lO 

400     " 

^i 

it 

II 

J3 

"  12 

«l         tt 

500     " 

si 

ti 

II 

14 

"   12 

35°     '' 

3f 

(( 

II 

i.S 

Mch.    6 

55° 

6A 

ii 

23 

13.80 

S.61 

16 

"       6 

550 

4* 

23 

13-75 

S.60 

it 

17 

"       7 

250 

Si 

21 

1304 

4-7.S 

18 

'       7 

=5°     ' 

SA 

21 

12.50 

4-87S 

>9 

;   9 

25°     " 

4i 

25 

12.79 

5-59 

U 

20 

9 

'*     " 

350     " 

t^i 

" 

21 

12.27   , 

3-94 

21 

"  10 

'*      " 

200     " 

4.t 

'* 

25 

14.08 

3-74 

22 

"  10 

200     " 

4i 

22 

13-69  i 

3-25 

44 


THE  COMPOSITION^OF  EXPIRED  AIR, 


The  determinations  of  tlie  proportions  of  CO,  and  of  O  in  the  air  of  the  jar  at  the  end  of  the 
experiments  were  made  with  the  Bunte  gas  burette  represented  in  Fig.  6.  For  rapid  determinations 
this  apparatus  gives  quite  satisfactory  results,  and  one  soon  learns  to  manage  it  easily  and  obtain 
results  concordant  witli  those  obtained  by  other  methods.  It  is  not  claimed  that  the  results  so 
obtained  arc  absolutely  accurate,  but  any  error  resulting  from  the  use  of  this  burette  is  a  constant 
one  in  all  the  air  analyses  for  the  different  experiments  reported  on,  and  is  without  influence  on 
the  results  obtained. 

a  represents  the  burette  proper  ;  the  upper  portion  is  of  larger  size  than  the  lower,  which  is 
marked  with  a  scale  extending  from  zero  near  the  bottom  to  loo  c.  c.  just  below  the  expanded  por- 
tion  above,   and  from  the  zero  mark  down   to   lo   c.  c.  near  the  lower 
extremity  of  the  tube.     The  capacity  from  the  loo  c.  c.  mark  to  the  three- 
way  stop-cock,  b,  closing  its  upper  end,  is  50  c.  c. — making  the  entire  ca- 
pacity of  the  tube  160  c.  c.     The  lower  end  is  closed  by'means  of  a  simple 
glass  stopcock,  c.    e  represents  a  small  cup  at  the  top  with  marks  at  20  and  . 
25  c.  c.  respectively,  thus  facilitating  the  measurement   of  the  contained 
volume  of  gas  at  a  constant  pressure  of  known  amount  of  water  in  the  cup. 
/represents  an  iron  stand  to  which  the  burette  is  firmly  clamped. 
(/  represents  a  glass  tube  of  wider  calibre  surrounding  the  burette, 
filled  with  water  and  serving  as  a  water-jacket  to  prevent  rapid  changes 
in  temperature  of  the  gases  under  examination. 

METHOD    OF    USING    BUNTE'S    GAS    BURETTE. 


d 


f 


The  burette  is  filled  with  water  and  the  three-way  stopcock  closing 
its  upper  end  is  so  turned  as  to  communicate  through  it  with  the  external 
air,  or  with  the  vessel  containing  the  air  to  be  analyzed,  by  means  of  a 
short  piece  of  rubber  tubing  connecting  this  stopcock  with  such  vessel. 
By  opening  the  stopcock,  closing  its  lower  end,  some  of  the  water,  say  150 
c.  c,  is  allowed  to  flow  out,  and  the  air  or  gas  to  be  analyzed  flows  in  to 
take  its  place.  When  the  desired  amount  of  the  sample  of  air  has  been 
taken,  the  lower  stopcock  is  quickly  closed  and  the  three-way  stopcock  is 
turned  half-way  round,  thus  bringing  it  in  communication  with  the  small 
cup  at  the  top,  which  should  also  be  filled  with  water  to  its  25  c.  c.  mark. 
The  pressure  of  the  contained  air  is  now  equalized  and  the  communication 
with  the  cup  is  closed.  A  few  drops  of  water  always  lodge  just  below  the 
upper  stopcock  ;  these  must  be  dislodged  by  gently  tapping  the  iron  stand 

r II — \  on  the  floor.     In  a  few  minutes  the  volume  of  air  may  be  read  off.     The 

\  'X      burette  is  then  connected  at  its  lower  end  with  a  Chapman  water  pump  and 

W^^a^^H^HM^^  a  portion  of  the  water  in  it  is  drawn  off.  The  water  in  the  cup  is  then  poured 
out  and  about  10  c.  c.  of  a  40  per  cent,  solution  of  sodium  or  potassium  hy- 
droxide poured  into  it,  and  in  turning  the  stopcock,  this  flows  in  to  take  the 
place  of  the  water  just  removed.  The  fluid  and  air  in  the  burette  are  now 
gently  agitated,  at  intervals,  for  five  minutes,  the  cup  is  again  filled  with  water  to  the  25  c.  c.  mark, 
the  stop-cock  again  opened,  and  the  pressure  of  the  gas  equalized.  If  any  of  the  water  flows  into 
the  burette  more  must  be  poured  into  the  cup  to  retain  the  gas  under  the  original  pressure  of  25  c.  c. 
of  water  in  the  cup.  This  part  of  the  operation  requires  some  care  and  practice  in  order  to  prevent 
the  escape  of  any  of  the  contents  of  the  burette  or  the  entrance  of  external  air.  When  the  pressure 
is  again  equalized  the  volume  of  gas  is  again  read  oft",  the  reduction  in  volume  representing  the 
amount  of  COo  absorbed,  this  is  readily  calculated  to  the  per  cent,  of  the  original  volume  of  gas. 

The  burette  is  now  once  more  attached  to  the  Chapman  water  pump  to  remove  a  portion  of 
the  fluid  in  the  burette.  About  10  c.  c.  of  a  12  per  cent,  solution  of  pyrogallic  acid  is  poured  into 
the  cup  and  allowed  to  flow  in.  The  fluid  and  gas  are  gently  agitated,  at  intervals,  during  five 
minutes,  the  pressure  equalized  as  before,  the  volume  of  gas  read  off,  and  the  calculations  for  O. 
made  as  before.     In  most  instances  N.  is  the  only  gas  remaining. 


Fig.  6. — Bunte's  Gas 
Burette  (Xi'n). 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  45 

From  the  determinations  of  the  proportions  of  COo  and  of  O.  in  the  air  of  the  jar,  after  death 
of  the  animal,  in  the  Hammond  experiments,  it  is  evident  that  two  factors  were  operative  in  killing 
it.  These  were  the  low  percentage  of  O.  present  and  the  high  percentage  of  COj,  which  the 
arrangements  instituted  for  the  absorption  of  this  gas  had  failed  to  remove.  In  a  short  time  the 
e.\terior  of  the  sponges  became  coated  with  BaCOj  while  the  Ba(HO)o  in  the  interior  became 
inoperative.  This  can  be  demonstrated  by  determining  the  alkalinity  of  the  fluid  expressed  from 
the  sponges,  at  the  end  of  the  experiment,  with  solution  of  oxalic  acid.  Another  fact  which 
substantiates  such  a  conclusion  is  that  of  the  clouding  of  the  Ba(H0)5  in  the  Geissler  potash  bulbs 
ipiito  early  in  the  experiment  from  the  COj  in  the  air  aspirated  from  the  jar  in  sujjplying  fresh  air. 
While  the  solution  of  Ba(HO)3  used  in  the  sponges  was  twice  the  strength  of  that  usually  employed 
in  COj  determinations  in  the  Pettenkofer  fliask  method,  the  amount  of  solution  which  can  be  taken 
up  by  the  sponges  of  the  size  used  (about  lo  c.  c.  each)  is  entirely  too  small  to  absorb  more  than  a 
fractional  part  of  the  COo  generated  by  an  animal  during  the  lime  of  an  experiment. 

The  mode  of  death  in  these  experiments  presented  such  a  close  similarity  to  that  noted  in 
cases  of  COo  poisoning,  under  other  circumstances,  that  it  was  impossible  to  distinguish  it  from 
death  produced  by  that  gas.  Judging  from  the  air  analyses  at  death  of  the  animals,  from  the  con- 
stancy of  the  symptoms  and  the  close  similarity  of  the  gaseous  contents  of  the  jars  at  death  of  the 
animals,  and,  besides  these,  the  absence  of  any  positive  indications  of  the  presence  and  action  of 
other  poisonous  expiratory  products  as  manifested  either  by  the  action  of  the  animals  or  the  mode 
in  which  death  took  place,  it  is  safe  to  conclude  that  the  low  percentage  of  O,  together  with  the 
high  percentage  of  COj,  in  the  atmosphere  of  the  jars,  were  the  principal  causes  of  death.  'I'he 
mode  of  death  differed  in  no  particular  from  that  noted  in  the  case  of  animals  dying  in  the  closed 
vessels,  in  the  "  Brown-Secjuard  "  experiments,  or  in  those  made  with  artificial  gaseous  mixtures 
where  sufficient  oxygen  was  present  to  support  life  for  several  hours.  Another  fact,  observed  like- 
wise in  all  the  other  forms  of  experiment  reported  on,  was  the  prompt  revival  of  the  animals  when 
removed  from  the  jars  and  sup[)lied  with  fresh  air.  In  exceptional  cases,  where  the  animal  was  not 
removed  until  death  was  certain  to  take  place  in  a  very  short  time,  the  revival  of  the  animal  did 
not  follow  on  removal  from  the  jar,  but  death  sujjervened  at  a  shorter  or  longer  period  after 
removal.  The  failure  of  these  animals  to  revive  might  be  attributed  to  the  presence  of  ante-mortem 
clots  within  the  heart  cavities  produced  by  the  long-continued  respiration  of  such  high  percentages 
of  Coj  as  existed  in  the  atmosphere  of  the  jars  in  this  and  the  other  experiments.  The  prompt 
revival  of  the  animals  removed  from  the  jars  a  little  earlier  appears  to  be  an  additional  indication 
that  the  symptoms  produced  in  these  experiments  had  been  due  to  the  relative  proportions  of  O 
and  COj  present  in  the  atmosphere  which  the  animals  breathed.  The  effects  of  an  organic  volatile 
poison  would  not  allow  such  rapid  recovery,  and  would  most  probably  manifest  itself  by  continued 
ill-health  on  the  part  of  the  animals  subjected  to  it. 

Some  animals  vitiated  the  contained  air  more  rapidly  than  others,  so  that,  while  there  is  a  close 
relation  between  the  composition  of  the  atmosphere  at  the  end  of  the  experiments,  it  is  evident  that 
the  degree  of  respiratory  interchange  determined  the  duration  of  life  for  each  individual.  The 
room  temperature  for  these  experiments  was  very  nearly  constant — 18°  to  25°  C. 

A  further  attempt  was  made  by  modifying  the  apparatus.  This  modification  is  shown  in  Fig. 
7.  Here  the  COj  is  absorbed  by  passing  the  air,  issuing  from  the  bell-jar  containing  the  animal, 
through  five  Pettenkofer  absorption  tubes,  each  containing  100  c.  c.  of  a  strong  solution  of  Ba(HO), 
[10  g.  Ba(HO)»  -f  SHjO  to  i  L.].  In  addition  to  this,  the  air  is  passed  through  two  Pettenkofer 
tubes,  each  containing  100  c.  c.  of  Buchner's  alkaline  pyrogallate  solution,  to  remove  some  of  the 
O  from  the  air.  The  moisture  is  absorbed  by  CaClj  placed  in  a  shallow  vessel,  covered  with  a 
perforated  porcelain  plate,  in  the  bottom  of  the  bell-jar. 

DESCRIPTION    OF    THE    Al'I'.^R.VTUS    USEU    IN    THE    MODIFIED    "  HAMMOND"    EXPERIMENT,  FIG.  7. 

a  represents  a  one-litre  bell-jar  resting  on  a  ground-glass  plate,  and  contains  a  shallow  vessel  with 
CaClj.  The  vessel  containing  the  CaClj  is  covered  with  a  perforated  porcelain  plate  on  which 
the  mouse  under  experiment  is  placed. 


46 


THE  COMPOSITION  (JK  KXl'IRKD  AIR, 


b  b  are  the  two  aspirating  flasks,  of  four  litres'  caijatity,  partially  filled  with  saturated  salt  solu- 
tion. By  reversing  their  positions  these  aspirators  give  a  continuous  current  of  air.  The  rubber 
cork  closing  the  top  of  these  flasks  carries  two  glass  tubes  with  glass  stopcocks,  and  the  apparatus 
is  so  constructed  as  to  maintain  the  air  current  in  the  same  direction  by  closing  one,  and  opening 
the  other,  of  these  glass  stopcocks  when  the  flasks  are  reversed  in  their  positions. 

l"he  Pettenkofer  tubes  containing  the  Ba(HO)2  are  attached  to  the  stative  c,  and  those  con- 
taining the  pyrogallate  solution  to  the  stative  li. 

e  represents  a  stopcock  in  the  tubing  connecting  the  aspirators.  This  serves  to  control  or 
arrest  the  aspiration. 


Fig.  7.  —  Modified  Hammond  Apparatus  (devised  by  Abliott). 

The  results  obtained  with  this  modification  of  the  apparatus  are  shown  in  Table  H.  The  same 
animal  was  used  in  each  of  the  six  different  experiments  performed,  and  it  failed  to  succumb  to  the 
conditions  present  in  any  of  them.  In  the  later  experiments,  in  which  the  animal  was  placed  in  a 
one-litre  bell-jar,  it  failed  to  reduce  the  proportion  of  O  in  the  volume  of  air  within  the  apparatus 
(about  six  litres)  to  such  an  extent  as  to  endanger  its  life,  even  with  the  additional  reduction  of  O 
taking  place  in  the  two  Pettenkofer  tubes  containing  Buchner's  solution  of  alkaline  pyrogallate. 
The  percentage  of  CO.,  remained  quite  low  through  the  absorption  by  the  Ba(HO)2  in  the  five 
Pettenkofer  tubes.  The  construction  of  the  apparatus  permitted  the  continuous  circulation  of  the 
air  within  the  apparatus  so  that  the  animal  was  constantly  breathing  air  that  had  been  breathed  and 


Table   H. 
modified  "  hammond  "  experiment. 


Examination 

No. 

Date. 

Animal. 

Weight. 

Aspiration- 

Number  of 
absorbers. 

Capacity 

Time. 

of  air. 

Remarks. 

CO,. 

0. 

1894 

Grams. 

Hours. 

f« 

^ 

1 

Oct.  24 

White 
mouse. 

23 

Continu- 
ous. 

5Ba(HO)2 

tubes. 

4000  c.c. 

7i 

Mouse  quite  sick. 

2 

"     2S 

" 

ti 

(( 

n 

((           i( 

81 

((                     ((              n 

^ 

"     26 

^^ 

it 

** 

li 

1000  c.  c. 

6 

U                       11                11 

4 

"     27 

11 

i( 

i( 

J5Ba(HO)2 
(  2  Pyro. 

((          (I 

4l 

■33 

9-44 

Previous  aspiration 
2  hours. 

S 

"     31 

(( 

(( 

ti          li 

7 

— 

I8-3S 

Previous  aspiration 
12  hours. 

6 

Nov.   3 

11 

(( 

n 

ii 

i(           (( 

61- 

Previous  aspiration 
10  hours. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


47 


rebreathed  before.  The  direttion  of  the  air  current  through  the  apparatus  is  shown  by  the  position 
of  the  arrows  in  the  figure.  Ky  changing  the  position  of  the  as|)irating  flasks,  and  turning  the  stop- 
cocks in  the  glass  tubing  inserted  through  the  stoppers  closing  the  upper  openings  of  the  aspirators, 
the  current  was  maintained  in  the  same  direction  as  before,  and  the  entrance  of  external  air  was 
thereby  prevented. 

The  results  obtained  show  that,  with  the  absorption  of  the  COo  as  generated,  the  mouse  re- 
mained relatively  comfortable  in  the  atmosphere  present  and  that  no  deleterious  effects  developed 
from  the  continued  rebreathing  of  the  air  confined  within  the  apparatus.  The  animal  seemed  to 
be  somewhat  oppressed  toward  the  close  of  each  experiment,  but  revived  quickly  after  removal 
from  the  apparatus. 

The  air  contained  in  the  two  aspirating  flasks  was  retained  each  time  in  the  later  experiments. 
Consecpiently  in  these  exiierinients  the  fresh  air-supply  comprised  only  that  which  was  enclosed  in 
the  Pettenkofer  tubes,  the  rubber  connecting  tubes,  and  in  the  bell-jar  containing  the  animal.  In 
several  of  the  later  experiments  the  volume  of  air  within  the  apparatus  was  aspirated  continuously 
through  all  its  parts  for  some  hours  before  beginning  the  experiment.  In  this  manner  the  pure 
air-supply  was  reduced  to  one  litre,  the  amount  of  air  in  the  bell-jar  containing  the  animal. 

V. — Experiments  to  determine  the  proportions  of  COo  and  of  O  in  the  air  of  a  glass  vessel  in 
which  small  animals  (mice  and  birds)  had  remained  until  death  was  produced,  and  the  effects  of 
different  temperatures  upon  the  duration  of  life  and  on  the  composition  of  the  residual  atmosphere 
after  death  in  such  cases. 

The  results  obtained  in  these  experiments  are  shown  in  Table  I.  .-Vt  the  room  temperature 
death  did  not  take  place  until  the  amount  of  oxygen  present  was  too  low  to  sujjport  life.  At  a 
higher  or  lower  temperature  there  was  a  slightly  shorter  duration  of  life,  varying  with  the  amount 
of  increase  or  reduction  of  the  temperature. 

T.\BLE    I. 
EXPERIME.VTS    WITH    .^NI.MAI.S    I-\    CLOSED    VESSELS— ATMOSPHERIC    AIR. 


No. 


I 

2 

3 
4 

5 
6 

7 
8 

9 

lO 

II 

12 

'3 
'4 


»5 
i6 


Date. 


]  Capacity 
I  of  the  jar. 


■893 
Nov.  27  1000  c.  c. 

"    28 1     " 
2000 


Dec. 


1000 


"    14 

1894 
Jan.  26 

"    27 

"    30  2000 
Feb.    I       " 

"     2      " 


9 

9  " 

.7        ••    13  " 

18  "    13  " 

19  Mch.28  7000  c 

20  "29  " 
2.  "  30  " 
22  ,     "    3'  " 


Tempera- 

ture. 

Hours. 

29-5°  c. 

4 

25-  °  C. 

3it 

23.5°  c. 

5 

23-5°  C. 

7i 

8* 

29.  °  C. 

3i 

3°-  °  C. 

4 

30.5°  c. 

4i 

31.  °c 

4 

31.  °c. 

4* 

7-5°  C. 

7 

5-  "C. 

H 

25.5°  C. 

li 

24.  "  C. 

2 

2A 

27-5°  c. 

2j 

27-5°  C. 

2i: 

30.  °  c. 

9 

29-5°  c. 

7i 

11.5°  c. 

9J 

12.  °  C. 

H 

Exam. 

of  air. 

Animal. 

Weight. 

CO,. 

0. 

Mouse. 

Grains. 
i8i 

13.818 

^ 

i8i 

2  2|- 

17.66 

ti 
it 
tt 

III 

19* 

21 

17.3° 
13.12 

12.00 

8.60 

tt 
ti 

II 
21 

12.00 

8.60 

tt 

12.60 

8.00 

10.00 

9.20 

13.20 

6.40 

tt 

11.90 

7-50 

Sparrow. 

12-75 

5.86 

it 

24 
23 

13.28 
13-485 

4.89 
7-37 

n 

23 

22 

13.00 
87-97 

6.929 
5-534 

Remarks. 


Cold-water  cloths  applied 
to  the  outside  of  the  jar 
at  temperature  of  11°  C. 


48 


THE  COMPOSTTION  OF  EXPIRED  ATR, 


The  effects  of  temperature  upon  the  duration  of  Hfe  in  a  confined  si^ace  (and  even  in  the  open 
air)  are  better  shown  in  tlie  repetition  of  Richardson's  experiments  (8),  as  presented  in  Table  J. 
The  results  obtained  in  these  experiments  show  that  the  duration  of  life  is  very  perceptibly  short- 
ened through  the  influence  of  a  higher  as  well  as  of  a  lower  temperature  than  i8°  to  20°C. 


Table  J. 
Richardson's"  experiment. 


Exam. 

of  air. 

No. 

Date. 

Animal. 

Weight. 

Capacity 
of  jar. 

Tempera- 
ature. 

Atmos- 
phere. 

Time. 

Kemarlcs. 

COs 

0. 

1894. 

Grams. 

c.  c. 

^ 

^ 

I 

Nov.  5 

White 
mouse 

22 

600 

48°  c. 

Air. 

5  min. 

1.90 

18.25 

Died. 

2 

"    5 

(( 

22 

(( 

8.5"  " 

*' 

2^  hrs. 

12.7 

3-7 

(( 

3 

5 

a 

2li 

" 

0.0"  " 

" 

t      " 

ir.4 

6.05 

" 

4 

"    5 

ti 

2oi 

16.2"  " 

3      " 

>3-'5 

2.6 

Flask  plunged  in  hot 

S 

"    6 

n 

16 

So.°  " 

16  min 

water — open  at  top. 
Same   as  in   No.    4. 

6 

"    6 

Gray 

mouse 

20 

1000 

42.°  " 

3°  " 

Remained  alive. 
Same  as    in  Nos.  4 

7 

"    6 

i( 

12 

a 

S8.°  " 

t( 

21   " 

and  5.     Died. 
Rapid  current  of  air 

8 

"    6 

White 
mouse. 

600 

48.°  " 

76.59  i  0. 

7  " 

aspirated     through 
the  flask. 

9 

"    6 

it 

22 

(( 

19.5°" 

2J.41  ^  N. 

4|hrs. 

Same  flask  as  No.  9. 

lO 

"    6 

(( 

90.8  -f,  0. 

2omin. 

22.36 

39-44 

Mouse   introduced 
at  death  of  No.  9. 

II 

"    9 

it 

16 

ii 

,9.°  " 

9.2  ^  N. 

4ihrs. 

Same  flask  as  No.  11. 

12 

"    9 

<i 

it 

90.8  ^  0. 

2     " 

25.20 

47.26 

After  death  of  No. 
1 1. 

13 

"    9 

Gray 
mouse. 

2  [ 

a 

13.°  " 

9.2  fo  N. 

3i" 

14 

"    9 

" 

ii 

20.°  " 

90.8  fo   0. 

26min. 

28.01 

After  death  of  No. 
>3- 

15 

"  10 

White 
mouse. 

18 

u 

5°-°  " 

9.2  %  N. 

3ihrs. 

i6 

"   10 

a 

21 

39.5°" 

90.8  fo  0. 

■^  " 

1934 

55-03 

Afterdeathof  No.  15 

17 

"   10 

ii 

16 

(1 

-4.5°  " 

9.2  %  N. 

54min. 

i8 

"   10 

n 

22 

'* 

-1.0°  " 

40  " 

2493 

60.65 

AfterdeathofNo.  17 

19 

"   '3 

a 

12 

(( 

18.     " 

Air. 

2.ihrs. 

20 

"   13 

i( 

'3 

u 

18.^" 

I  min. 

14-47 

4.07 

Afterdeath  of  No.  19 

21 

"  13 

(( 

12 

" 

-4.0°  " 

Air. 

55  " 

22 

"   13 

13 

(( 

-7.5°" 

34" 

10.76 

7-45 

Afterdeathof  No.  21 

An  interesting  condition  noted  in  autopsies  upon  a  number  of  the  animals  that  succumbed  to 
the  conditions  in  the  "  Richardson  "  experiment  was  that  of  the  blood  in  the  heart  of  the  animal. 
In  the  cases  where  death  supervened  in  a  short  time,  the  heart  blood  was  fluid  and  seemed  to  lack 
the  power  of  coagulation,  while  in  those  cases  in  which  death  resulted  after  several  hours'  confine- 
ment in  the  flask,  the  cavities  of  the  heart  contained  firm,  dark  clots  of  blood.  This  condition  of 
the  blood  was,  no  doubt,  due  to  the  influence  of  the  CO,  generated  by  the  animal  during  the 
experiment. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


49 


CHART  I. — Showing  Relative  Proportions  of  COj  and  of  O,  and  the  Relative  Duration  of  Life  in  the 

Experiments  in  Closed  Vessels. 


Key 


Represents  relative  per  cent,  of  CO.  at  close  of  exp. 

X  — X—        "  o"      " 

. "  "         duration  of  life. 

I  0 — o "  "        room  temperature. 


/ 

2 

3 

*■ 

s 

b 

7 

a 

9 

/O 

II 

/a 

/3 

1* 

IS 

16 

17 

IS 

19 

2.0 

Zl 

2Z 

i)0 

■'S 

a.» 

fO 

'■>     ^ 

_     u 

3    ? 

60  S 

}.5 

o 

—  9 

-     ? 

'so^ 

ZS  1 

-^ 

\ 

i-y~ 

\ 

^ 

-^' 

-^ 

\ 

-    o 

i-0    Q 

2aS 

"^ 

— 

Cr- 

\ 

/ 

' 

N>- 

\ 

6    ?i 

30  o" 

-    « 

\ 

/ 

\ 

-      i 

7    o 

20^ 

-    I- 

\ 

— 1 

■J. 

5? 

\ 
,      0 

-J 

U^ 

— s 

-      Q 

* 

:    i 

1    1 

;    i 

i  i 

!  1 

1     i 

\      i 

;.  1 

;     k 

A 

>      i 

Chart  I.  shows  the  relative  duration  of  life,  the  relative  proportions  of  ("0„  and  of  O  at  death 
of  the  animal,  in  the  experiments  with  animals  in  closed  vessels  containing  atmospheric  air. 

CII.XRT  II. — Showing  Relative  DuR.vrioN  of  Life,  Proportionsof  N  and  O  .at  Beginning  of  Experiments, 
with  the  Temperature  of  the  Atmospheres  in  the  "  Richardson  "   Experiments. 


Kcv 


— X— X— X 


Represents  relative  per  cent,  of  X. 

' O. 


duration  of  life, 
temperature  in  the  flask. 


1 

2 

3 

«. 

5 

6 

7 

8 

9 

10      II 

IZ 

/J 

/f 

IS 

16 

/7 

/a 

/5 

20 

Zl 

22 

ffC 

70 

1 

1 

1 

I 

1 

1 

1 

M 

0 
60^ 

\ 

2^ 

7.^ 

; 

A 

1 

? 

n   I' 

\ 

-3t 

-     1 

\\ 

f 

1/ 

i\ 

1 

Al 

\ 

i 
1 

i       1 

h^ 

-30% 

i\ 

1 

;   \ 

/ 

i 

\ 

; 

"2 

10'^ 

i 

/ 

1 

Vi 

i 

y 

\ 

1 

;^ 

10  t. 

\ 

/ 

1 

; 

i 

— O— J- 

"^ 

-! 

/° 

\ 

.    Y 

h 

A 

'soot 

-      Q. 

0  := 

;\ 

f/ 

; 

1    I 

M 

y 

^ 

\    , 

K 
-      'T 

9  «: 

10 

-    k 

10 

;    1 

i    1 

1       t 

1      ■• 

■  i 

'   1 

■    1 

:  t 

;  1 

!      i 

Y 

. 

iU 

.-d. 

i      1 

:^ 

--cf 

-     =3 

- 

- 

1    } 

J «. 

i_i 

1  i 

;      i 

il 

;   i 

'. 

j 

. 

u 

1 
i 

Chart  II.  shows  the  relative  duration  of  life,  the  relative  proportions  of  N  and  of  O  at  the 
beginning  of  each  of  the  "  Richardson  "  experiments,  also  the  temperature  curve  for  the  entire 
series. 


50 


THE  COMPOSITION  OF  EXPIRED  AIR, 


Tablk   K. 
experiments  with  akjti'tcial  atmospheres. 


Before  experiment. 

After  exper 

ment. 

KespiratAy 

Dale. 

Animal. 

Weight. 

Capacity 

Time  of 
experi- 

Ouotient 

No. 

"cOj 

0    J  1. 

?' 

« 

ment. 

% 

i 

91 

0. 

• 

COs. 

0. 

N. 

CO,. 

0. 

N. 

1894. 

Grams. 

c.c. 

I 

April  30 

Mouse. 

2280 

4.90 

95-1° 

30  sec. 

.02 

4  4° 

95.40 

0.0045 

2 

"     30 

" 

84.00 

16,00 

1 1 J  hrs. 

20.00 

58.73 

16.91 

°-3405 

3 

May    25 

Rabbit. 

1920 

37,000 

.04 

20  7 

79.26 

51:      " 

14.87 

4.09 

81.04 

3-6356 

4 

June     6 

Guinea- 

pig- 

473 

40CO 

.04 

20.7 

79.26 

'f      " 

15.26 

4.29 

80.45 

3-5571 

5 

"        4 

" 

565 

.68 

5-39 

93-93 

43  min. 

8.50 

2.31 

89,19 

3-6796 

6 

May      5 

Mouse. 

2280 

8397 

16.03 

13I  hrs. 

25.83 

58.65 

14.76 

0.4404 

7 

;:    5 

" 

83-97 

16.03 

i5i    " 

21.06 

61.78 

17.16 

0.3408 

8 

"           2  1 

18 

11-35 

88.65 

3i      " 

6.56 

4.14 

89.30 

1-5845 

9 

"           21 

IS 

11-35 

88.65 

4j-      " 

7-43 

358 

89.00 

2-0754 

lO 

"          21 

(( 

17 

n 

11-35 

88.65 

4^      " 

7-52 

3.16 

89.22 

2-3797 

II 

21 

9-°5 

9°-95 

6f      '' 

5-41 

3-34 

91-25 

1. 6197 

12 

"           21 

H 

9-°5 

9°-95 

loi    " 

4-51 

2.84 

92.65 

1.5880 

'3 

"           2  1 

1 1 

9-05 

9°-95 

6f"    " 

5-17 

2.87 

91.96 

1-8013 

14 

28 

i6 

8.23 

9'-77 

4      ." 

4.18 

2.52 

93-3° 

1.6587 

'5 

28 

8 

8.23 

91.77 

I  min. 

•63 

6.48 

92.89 

0.0972 

i6 

28 

15 

8.23 

9'-77 

si  hrs. 

3-85 

2.54 

94-6  T 

1-5157 

■7 

June     I 

22 

4( 

5-7° 

94.3° 

4  min. 

■58 

4.91 

94-5' 

0.1181 

iS 

I 

17 

5-70 

94-30 

2    " 

•77 

5-4° 

93-83 

0.1425 

19 

May    26 

12 

5-7° 

94.3° 

20 

"       24 

10 

•58 

5-40 

94.°2 

3  min. 

21 

"       24 

8 

-58 

5-4° 

94.02 

2    " 

22 

"       24 

8 

-58 

5-4° 

94.02 

2^" 

-79 

5-75 

93-46 

0-1273 

23 

June     I 

" 

1 1 

** 

12.03 

21.61 

66.36 

si  hrs. 

18.91 

24 

I 

(( 

10 

li 

12.03 

21.61 

66.36 

8|    " 

21.02 

25 

April  29 

" 

<1 

13-1° 

3-70 

82.90 

30  sec. 

13-40 

3.70 

82.90 

3.6216 

26 

May    10 

14.65  22.00 

63-35 

7     hrs. 

2465 

11.40 

64-95 

2.1622 

27 

"      10 

14-65 

22.00 

63.35 

81     " 

25.10 

10,00 

64.90 

2.5100 

28 

"      10 

14-65 

22.00 

63-35 

8|    " 

28.30 

7.40 

64.30 

3-8243 

29 

"      1 1 

Rabbit. 

1357 

37,000 

ri.28 

19.64 

6908 

8.;   " 

19.16 

4.27 

75-57 

4.4871 

30 

::  ^5 

175° 

22.40 

22.30 

55-3° 

5"     "    • 

20.19 

4.80 

75-01 

4.2062 

31 

'5 

Mouse. 

2280 

21.00 

12.00 

67.00 

2       " 

19.70 

8.93 

71-37 

2.2060 

32 

^5 

" 

21.00 

12.00 

67.00 

2|      " 

20.00 

8.41 

7157 

2.3781 

33 

.  ^5 

n 

21. 00 

12.00 

67.00 

5i    ". 

21.80 

6.54 

71.66 

3-3333 

34 

4 

21-95 

16.65 

61.40 

52  min. 

21.45 

15.7° 

6285 

1.3662 

35 

"  4 

21-95 

16.65 

61.40 

2{  hrs. 

23.15 

12.815 

6-3985 

1.8064 

36 

"  4 

21-95 

16.65 

6 1.40 

4j\  " 

22.60 

11.43 

65-87 

1.9772 

37 

June     8 

Rabbit. 

1400 

37,000 

17.00 

13-82 

69.18 

7i    " 

16.14 

2.97 

81.69 

5-4343 

38 

"   '■        9 

Guinea- 

pig- 

478 

4000 

15.00 

21  00 

64.00 

li    " 

16.07 

2-77 

81.96 

5,8014 

39 

"      II 

Gray  rat. 

Full 

grown. 

37,000 

17.81 

3-88 

88.25 

<i    " 

11.13 

8-55 

80.32 

1-3017 

40 

May    31 

Mouse. 

2t 

2280 

2547 

18.00 

56.63 

2     <i 

27.11 

16,20 

52.69 

1-6734 

41 

::  31 

19 

" 

25-47 

18.00 

56.53 

If    " 

27.47 

17-53 

55-°° 

1.5670 

42 

31 

16 

" 

25-47 

18.C0 

56.53 

4    " 

27.42 

16.83 

55-75 

I  6292 

43 

June   u 

Guinea- 

pig- 

758 

4000 

30.00 

21.00 

49.00 

I       " 

17.83 

2.77 

79.40 

6.4368 

44 

"      12 

Gray  rat. 

Half 

grown. 

a 

37-5° 

22.50 

40.00 

J I     " 

17.25 

4.63 

78.12 

3-7257 

45 

"      13 

Rabbit. 

2255 

37,000 

56-75 

43-25 

5      " 

20.40 

-3.71 

75-89 

5-4986 

46 

"      13 

Guinea- 

pig- 

742 

4000 

62.50 

21.25 

16.25 

H   " 

27.60 

4.39 

68.01 

6.2870 

47 

"      12 

Mouse. 

2280 

81.36 

18.64 

1  min. 

81.36 

1864 

4.3648 

48 

"      12 

(( 

81.36 

18.64 

1    " 

81.36 

18.64 

4.3648 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  51 

In  order  to  ascertain  whether  an  atmosphere  which  had  served  for  respiration,  once  or  oftener, 
affected  an  animal  differently  from  an  atmosphere  made  up  artificially  from  pure  gases  to  the  same 
proportions  as  found  in  the  analysis  of  the  atmos]jhcres  in  the  different  experiments  reported  on,  a 
series  of  experiments  was  undertaken  to  determine  the  effects  of  gaseous  mixtures  made  up  of 
varying  proportions  of  COj,  O,  and  of  N.  The  results  obtained  in  this  series  of  experiments  are 
shown  in  I'able  K,  giving  the  capacity  of  the  jar,  the  weight  of  the  animal,  the  com|)osition  of  the 
atmosphere  before  and  after  the  experiment,  and  the  duration  of  life  in  such  an  atmosphere.  The 
construction  of  artificial  atmospheres,  and  the  introduction  of  an  animal  into  such  an  atmosphere 
without  considerable  alteration  of  the  proportions  of  the  different  gases,  through  the  accidental 
introduction  of  3tmos|)heric  air,  was  not  always  found  an  easy  matter.  The  chief  difficulty  was 
unfortunately  a  fundamental  one,  in  that  the  COj  was  not  entirely  free  from  atmospheric  air  ;  the 
oxygen  contained  more  than  lo  per  cent,  of  N  ;  while  the  attempt  lo  obtain  pure  N  from 
atmospheric  air  by  means  usually  employed  for  this  purpose  — burning  out  the  O  with 
phosphorus — gave  variable  results  with  each  attempt,  the  proportion  of  O  remaining  after  the 
absorption  of  the  P0O5  usually  ranged  from  2  to  5  per  cent.  Under  these  circumstances  it  will  be 
seen  that  there  was  an  almost  insurmountable  difficulty  to  the  construction  of  an  atmosphere  having 
the  exact  proportions  of  the  different  gases  predetermined  for  it,  and  abundant  evidence  of  this 
difficulty  was  obtained  from  analyses  of  the  mixtures  after  sufficient  time  had  been  allowed,  as  was 
supposed,  for  the  diffusion  of  the  gases. 

The  thorough  diffusion  of  the  components  of  gaseous  mixtures  appears  to  be  a  slow  process. 
Twenty  four  hours,  or  longer,  was  usually  allowed  for  this  to  take  place,  yet  from  the  variable 
lengths  of  time  during  which  animals  of  the  same  size  and  apparently  possessing  the  same  amount 
of  vitality  could  survive  in  atmospheres  of  equal  volume  made  up  from  the  same  mixture,  and  the 
variable  proportions  of  the  different  gases  found  on  analysis  after  death  of  the  animals  exposed  to 
these  atmospheres,  show  that  perfect  diffusion  had  not  always  taken  place.  These  discrepancies 
in  the  construction  of  the  gaseous  mixtures  are  to  be  regretted,  though  they  are  not  great  enough 
to  vitiate  the  value  of  the  experiments  taken  as  a  whole.  The  positive  character  of  the  results  is 
too  evident  to  allow  these  difficulties  to  have  much  weight. 

There  is  an  uncertain  feature  in  the  determinations  of  the  proportions  of  COo  in  the  gaseous 
mixtures,  after  death  of  the  animal,  in  those  instances  where  this  gas  was  originally  present  in  high 
percentages.  On  this  account  it  would  be  well  to  bear  in  mind  that  the  third  column  representing 
the  proportions  of  the  different  gases  present  at  death,  marked  N,  represents,  in  fact,  the  gases 
which  failed  to  be  absorbed  in  the  gas-burette  by  the  solutions  of  caustic  soda  and  of  pyrogallic 
acid  used  to  absorb  the  COo  and  O  present.  There  is  no  doubt  as  to  the  presence  of  the  propor- 
tions of  COj,  as  stated  in  the  different  experiments,  before  placing  the  animal  in  the  mixture. 
Whether  a  large  proportion  of  the  CO.  was  likewise  absorbed  by  the  animal,  it  is  impossible  to  say. 
There  is  no  probability  that  such  was  the  case.  A  part  of  the  loss  of  COo  may  also  be  accounted 
for  in  the  method  employed  in  making  the  gaseous  mixtures.  These  mixtures  were  made  by 
displacing  water  from  the  jars  which  were  to  contain  them.  The  water  may  have  taken  up  the 
COj  more  readily  than  the  other  gases,  especially  where  this  was  the  first  gas  introduced  into  the 
jar,  and  may,  therefore,  have  been  a  slight  source  of  variation  in  the  composition  of  the  mixture  ; 
yet,  it  seems,  from  analysis  made  just  before  placing  the  animal  in  the  mixture,  that  the  loss  in 
this  manner  was  very  small.  The  desired  proportion  of  COo  was  usually  present,  even  after 
twenty-four  hours  had  been  allowed  for  diffusion  to  take  place. 

Chart  III.  shows  the  results  obtained  in  these  experiments  as  to  the  relative  duration  of  life 
and  the  relative  proportions  of  COo  and  of  O  at  the  beginning  of  the  experiment,  as  well  as  at 
death  of  the  animal.  In  comparing  this  chart  with  Chart  I.,  it  must  be  remembered  that  in  this 
series  of  experiments  the  composition  of  the  atmosphere  was  a  different  and  variable  one,  while  in 
the  series  of  experiments  shown  in  Chart  I.,  the  composition  of  the  atmosphere  at  the  beginning  of 
the  experiment  was  invariably  the  same — i.f.,  atmospheric  air.  This  fact,  along  with  the  variations 
in  size  of  jar  for  different  animals,  ex])lains  the  longer  or  shorter  duration  of  life  in  this  scries  of 
experiments  as  compared  with  that  presented  in  Chart  I.     The  very  important  influences  of  these 


52 


THE  COMPOSITION  OF  EXPIRED  AIR, 


variations  must  be  kept  in   mind  constantly  in  comparing  these  two  charts,  as  well  as  in  comparing 
the  results  obtained  in  any  of  the  other  forms  of  experiment. 

CHART   III.— SnowiNr.    thi',    Rklative  Troi'ORTIons   of  C0„   and  O,  before  and  after  each  Experiment 
WITH  the  Relative  Duration  of  Life  in  the  Experiments  with  the  Artificial  Gaseous  Mixtures. 


r  ^—   ^^   ^^  Represents  relative  proportion  of  COo  before,  and 

Key  -    —  X  — X—  "  O 

^^^^^vM>~  *'  "      duration  of  life. 


after,  the  experiment. 


1 

2 

s, 

4- 

5 

6 

7 

5 

9 

/£? 

// 

IZ 

13 

/«• 

/5 

/6 

/7 

IB 

19 

2^ 

90 

90 

1 

Z 

a.   2 

r 

1 

^    ? 

70     P 

■     X 
7n  1^ 

X 

1 

■I 

X 

1 

6    *: 

^ 

to 

1 

% 

1 

I 
r 

^0  i 

■   ? 

so  "^ 

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1 

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X 

1 

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The  mode  of  death  in  these  experiments,  when  sufficient  O  was  present  to  support  life  for 
several  hours,  was  similar  to  that  noted  in  the  "  Hammond  "  experiments,  in  the  experiments  with 
atmospheric  air  in  closed  vessels,  and  in  the  "  Brown-Sequard  "  experiments,  and  could  not  be  dis- 
tinguished from  death  in  CO,  poisoning.  When  such  an  amount  of  O  was  not  present,  death  was 
often  almost  instantaneous,  following,  at  the  longest,  within  five  minutes  after  the  animal  was  placed 
in  the  jar.     After  a  few  gasps  and  several  violent  struggles,  life  became  extinct. 

A  number  of  the  animals  used  in  this  series  of  experiments  were  examined  post  mortem.  The 
gross  appearances  presented  in  these  animals  were  of  the  character  of  those  found  ordinarily  in 
cases  of  COj  poisoning.     Intense  venous  engorgement  was  noted   in   all   the  organs   and   tissues. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


53 


The  heart  invariably  contained  large,  firm  blood-clots,  dark  in  color,  extending  from  the  auricles 
into  the  ventricles.     This  was  usually  most  marked  on  the  right  side. 

Microscopic  examination  of  the  organs,  hardened  in  alcohol  and  mounted  in  celloidin,  pre- 
sented no  other  constant  conditions  than  those  brought  about  by  the  mode  of  death — the  extensive 
venous  engorgement.  The  very  slight  pathological  changes  noted  in  isolated  cases,  from  the 
rapidity  with  which  death  ensued  on  exposure  to  the  atmospheric  conditions  present,  must  be 
attributed  to  causes  antedating  the  time  of  the  experiment  by  a  considerable  period.  The  changes 
here  referred  to  were  mostly  of  the  nature  of  interstitial  changes  present  in  the  liver  and  kidneys- 
No  trace  of  the  poisonous  effects  of  any  other  respiratory  products  was  noted  in  any  of  the  animals 
examined. 

The  results  obtained  strengthened  to  a  satisfactory  degree  the  conclusions  drawn  from  the 
results  obtained  in  the  other  experiments  reported  on.  It  was  shown  that  in  the  absence  of  a  suffi- 
cient proportion  of  O  in  the  artificial  gaseous  mixture  to  support  life — at  least  5  per  cent. — the 
animal  speedily  succumbed.  On  the  other  hand,  COj  could  be  present  in  quite  large  proportions, 
as  long  as  sufficient  O  was  also  present  to  support  life  for  some  time,  and  no  untoward  effects  were 
manifested.  The  different  animals  used  in  these  experiments — sparrows,  rats,  mice,  guinea-pigs, 
and  rabbits — manifested  no  distinct  differences  in  susceptibility  to  the  conditions  present. 

VI. — Experiments  in  the  inoculation  of  animals  with  the  moisture  condensed  from  the 
exhaled  breath,  as  conducted  by  Brown-Sequard  and  d'Arsonval,  by  Hofmann-Wellenhoff,  and 
others.     Four  series  of  animals  were  inoculated  with  the  fluid  as  shown  in  Table  1.. 

Series  I. — The  fluid,  clear,  limpid  in  character  and  without  odor,  of  which  21  c.  c.  had  been 
collected  from  the  breath  of  a  healthy  person  on  December  5,  1893,  was  warmed  by  holding  the 
receptacle  containing  it  in  a  vessel  of  warm  water,  about  35^  C.  A  rabbit,  weighing  1870  g., 
received  ij  c.  c.  into  the  large  vein  at  the  margin  of  the  ear.  Another  rabbit,  weighing  1820  g., 
also  received  i|  c  c.  in  the  same  manner.  A  guinea-pig,  weighing  220  g.,  received  4A  c.  c.  into 
the  peritoneal  cavity.  A  second  guinea-pig,  weighing  280  g.,  also  received  4i  c.  c.  into  the  peri- 
toneal cavity.  A  third  guinea-pig,  weighing  220  g.,  received  4^  c.  c.  of  sterilized  distilled  water 
into  the  peritoneal  cavity  as  a  control. 

These  animals  were  kept  under  careful  observation  for  more  than  a  month,  and  as  nothing 
unusual  in  their  condition  presented  itself,  they  were  released. 

Series  II. — On  January  :8,  1894,  20  c.  c.  of  the  fluid  had  been  condensed  from  the  breath  of 
the  man  having  the  tracheal  fistula.  The  fluid  was  warmed  by  holding  the  receptacle  containing  it 
in  a  vessel  of  warm  water,  about  36°  C. 

Of  this  fluid  5  c.  c.  were  injected  into  the  peritoneal  cavity  of  each  of  three  white  rats  ;  a  fourth 
rat  receiving  5  c.  c.  of  sterilized  distilled  water  into  the  peritoneal  cavity  as  a  control  experiment. 

inoculations  with  condensed  fluid  of  expired  breath. 

Table  L. 
series  I. 


No. 

Date. 

Animal. 

Weight. 

Amount  of  fluid 
injected. 

Remarks. 

I 
2 
3 
4 
5 

'893 
Dec.  5 

It 

it 
it 

Rabbit 
Guinea-pig 

Grams. 

1870 

1820 

220 

280 

220 

if  c.c. 

If    " 
44    " 
4J    " 
4i    " 

Under  observation  over  a  month.     Healthy. 
(1               ((             t.             .(                 i* 

11               It             tt             ti                 tt 

i(               tt             tt             tt                 t( 

Control — inoculated  with    sterilized   distilled 
water. 

54 


TFIE  COMPOSITION  OF  EXPIRED  AlU, 


1894 

I 

Jan. 18 

White  rat 

•95 

5  ex. 

Still  alive  and  heallhy. 

2 

(i 

140 

5   " 

Hied  9-6,  1894,  from  other  causes. 

3 

It 

(( 

148 

5    " 

Still  alive  and  healthy. 

Control— inoculated    with    sterilized   distilled 

4 

it 

(t 

I  12 

5    " 

water. 

SERIES   III. 


I 

Feb.  2 

Rabbit 

1500 

7^  c.c. 

Killed  after  48  days. 

2 

i( 

ii 

2150 

10      " 

Still  under  observation.     Healthy. 

3 

a 

(( 

880 

5      " 

Died  after  28  days. 

Control^inoculated    with    sterilized    distilled 

4 

(( 

(. 

900 

5      " 

water. 

SERIES    IV. 


Mch.  30 


Rabbit 


II6I 

10  c.c 

1400 

10    " 

1759 

10    " 

'359 

10    " 

Still  under  observation.     Healthy. 
Killed  11-2,  1894.     Healthy. 

Still  under  observation.     Healthy. 


These  animals  were  under  close  observation  for  several  months  without  noting  any  alteration 
in  their  condition.  One  of  them  has  since  died  (Sepf.  6,  1894)  from  other  causes.  The  others 
continue  well. 

Series  IH. — On  February  i,  1894,  44  c.c.  of  the  fluid  had  been  collected  from  the  e.xhalations 
of  the  man  having  the  tracheal  fistula.  This  fluid  was  again  warmed,  as  before,  to  about  35°  C. 
and  injected  into  the  peritoneal  cavity  of  rabbits  as  follows  : 

No.  I.     Weight,  1500  g,,     75  c.c.  of  fluid. 
No.  2.  "  2150  g.,    ID. o  c.c.   "      " 


No.  3. 
No.  4. 


S80  g.,     5  o  c.c.  "     " 

900  g.,     5,0  c.c.  "  sterilized  distilled  water. 


Rabbit  No.  3  of  this  series  died  during  the  night  of  March  4,  1S94,  and  an  autopsy  held  the 
next  morning  showed  the  following  conditions*  : 

Young  female  rabbit.  Externally  :  Not  very  thin,  adipose  not  quite  used  up.  Internally  : 
On  opening  the  abdominal  cavity  the  organs  were  found  in  normal  position.  Stomach  and  large 
intestines  well  tilled.  Liver  slightly  enlarged,  no  spots  ;  shows  lobular  appearance  well  marked  ; 
rather  pale  in  color,  as  are  all  the  organs  and  tissues  (albino),  (iall  bladder  well  filled  with  pale 
bile.  Small  intestines  moderately  filled  ;  no  change  in  their  appearance  ;  Peyer's  patches  not 
enlarged.  Appendix  not  inflamed.  Spleen  not  enlarged.  Kidneys  normal  in  size.  Adrenals  small. 
Lungs  normal,  rather  pale.     Heart  rather  pale,  contracted  on  left  side,  right  side  filled  with  blood. 

Cultures  were  taken  from  the  liver,  spleen,  blood,  and  abdominal  fluid  and  all  proved  negative. 

Microscopic  examination  of  the  organs  :  Kidney  :  Presents  some  blood-vessels  which  contain 
an  increased  amount  of  white  blood  corpuscles.     Glomeruli  are  slightly  swollen,  showing  a  small 

*  Autopsy  made  by  Dr.  Olmsted. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  55 

amount  of  infiltration.  Slight  increase  of  connective  tissue  between  the  tubules.  Large  blood- 
vessels are  very  much  dilated.  Areas  of  slight  extravasation.  A  certain  amount  of  cloudy  swell- 
ing. Liver — Shows  large  number  of  small  areas  of  cell-death — necrotic  areas.  Breaking  up  of 
cells  and  fragmentation  of  the  nuclei,  which  is  almost  identical  with  the  conditions  found  in 
diphtheria.  Adrenals — No  change  apparent.  Spleen  —  No  change  apparent.  I'he  teased  heart 
muscle,  treated  with  acetic  acid,  shows  possibly  a  trace  of  fatty  degeneration.  No  "widespread 
ecchymosesand  hemorrhages  in  the  lungs  and  intestines  "  werefound,  as  reported  by  Brown-S^quard 
and  d'Arsonval. 

On  March  20,  1894,  rabbit  No.  i  of  tliis  series  was  killed  in  order  to  study  the  condition  of  its 
organs  and  compare  the  results  with  the  conditions  found  in  rabbit  No.  3.  Weight  before  death, 
1830  g.,  gain  330  g.     It  seemed  to  be  in  perfect  health. 

On  opening  the  abdominal  cavity  the  organs  were  found  in  normal  position.  No  increase  of 
peritoneal  fluid.  On  the  liver  a  number  of  points  (psorosperms  ?),  one  a  depression  1  mm.  in  depth, 
grayish-white  in  appearance,  were  noted  ;  mostly  on  the  left  lobe.  Several  other  small  areas- 
whitish  in  appearance,  sharply  limited  in  their  outline,  smaller  than  the  last,  not  distinctly  depressed, 
usually  two,  three,  or  more  together — were  found  scattered  over  the  upper  and  lower  surfaces  of 
the  liver.  The  liver  is  dark  in  color,  lobules  well  marked  out  ;  of  about  normal  size  and  consistency. 
Cutiing  into  the  liver  there  is  the  usual  amount  of  hemorrhage.  Spleen — Small,  if  anything,  it  is 
contracted,  otherwise  of  normal  appearance.  Adrenals  appear  normal.  Kidneys — Embedded  in 
usual  amount  of  fat  Normal  in  size,  color,  and  consistency.  Small  echinococcus  cyst  in  the  great 
omentum,  and  another  in  the  liver.  Intestines  normal  in  appearance.  Heart  normal  in  appearance. 
Portion  of  muscle  teased  with  salt  solution  and  treated  with  acetic  acid  shows  no  fatty  change. 
Lungs  normal  in  appearance. 

Cultures  were  taken  from  the  peritoneal  fluid,  liver,  spleen,  kidneys,  and  blood.  All  proved 
negative. 

Microscopic  examination  of  the  organs  :  Liver — Contains  a  small  hemorrhage  at  the  depressed 
part  noted  at  autopsy.  The  other  spots  noted  are  found  to  be  entirely  superficial.  Slight  increase 
of  connective-tissue  elements.  Engorgement  of  a  capillary  noted.  Kidney — Nephritis  manifested 
by  some  congestion  of  vessels,  proliferation  of  the  connective-tissue  cells  between  the  tubules  and 
around  the  glomeruli  ;  an  occasional  glomerulus  being  quite  contracted.  Spleen  shows  an  increased 
amount  of  pigment. 

The  remaining  rabbits  of  this  series  have  continued  well  to  the  present  time. 

Series  IV. — On  March  30,  1894,  45  c.  c.  of  the  condensed  fluid  had  been  collected  from  the 
breath  of  a  healthy  person.  This  was  again  warmed  to  35°  C,  and  injected  into  the  peritoneal 
cavities  of  four  rabbits,  each  receiving  10  c.  c.  of  the  fluid  ;  their  weights  were  as  follows  :   1 161  g., 

"359  g.  '400  g-,  and  »759  g- 

On  November  2,  1894,  the  rabbits  of  this  series  having  remained  healthy,  Nos.  2  and  3  were 
killed  in  order  to  study  the  condition  of  their  organs,  and  determine  whether  they  presented  or- 
ganic lesions  traceable  to  the  fluid  injected.  They  were  in  perfect  health  as  far  as  might  be  judged 
from  their  a])pearances. 

On  post-mortem  examination  all  the  organs  in  these  animals  were  found  to  be  normal.  Nor 
was  any  abnormality  to  be  noted  in  microscopic  examination  of  the  organs. 

The  remaining  animals  of  this  series  continue  well  to  the  present  time. 

The  pathological  conditions  noted  in  the  cases  of  rabbits  Nos.  i  and  3  of  Series  III.,  are  not 
unusual  in  these  animals,  as  they  are  very  commonly  found  in  normal  animals  reared  in  the  labora- 
tory and  in  those  purchased  from  dealers.*  It  is  unsafe  to  infer,  therefore,  that  any  of  the  condi- 
tions noted  in  these  animals  were  due  to  the  action  of  the  fluid  injected. 

The  sterility  of  the  fluid  injected  into  the  animals  in  this  series  of  experiments  was  tested  each 
time  by  the  inoculation  of  |)ortions  of  it  into  tubes  of  melted  gelatin  ;  these  were  then  hardened 
according  to  Esmarch's  method.     In  two  instances  several  colonies  of  a  yellow  bacillus,  common  to 

•  This  fact  has  also  been  noted  by  Dr.  Abbott.     His  observations  have  not  yet  been  published. 


56 


THE  COMPOSITION  OF  EXPIRED  AIR, 


the  air  of  tlie  laboratory,  developed  in  the  cultures.  In  the  otlier  instances  tlie  cultures  remained 
sterile.  The  fluid  used  in  these  cultures  was  taken  from  the  portions  remaining  after  the  animals 
were  inoculated.  This  fact,  in  all  probability,  accounts  for  the  contaminations  noted.  There  is  no 
evidence  that  any  micro-organisms  were  carried  over  in  the  exhaled  breath  while  collecting  the 
fluids  for  the  inoculations.  The  nature  of  the  organisms  which  developed  in  these  cultures  indicates 
that  they  gained  entrance  to  it  while  the  fluid  was  being  warmed  and  inoculated  into  the  animals. 

VII. — Experiments  causing  animals  to  breathe  air  recently  expired  by  other  animals. 

'I'hese  experiments  are  designated  as  "  lirown-Sequard  "  experiments.  The  apparatus  used 
consists  of  a  series  of  bell  jars,  four  to  six  in  number,  connected  together  by  means  of  glass  and 
rubber  tubing,  and  so  arranged  that  a  continuous  current  of  air  is  conducted  through  the  entire 
series.     The  apparatus  is  shown   in   Fig,  8.     The  first  animal  receives  pure  air  only,  the  second 


Fig.  8. — Brown-Sequard  apparatus. 


animal  receives  the  air  coming  from  the  bell  jar  containing  the  first  animal,  the  third  that  coming 
from  the  second,  while  the  last  animal  receives  air  that  has  traversed  the  entire  series,  and,  conse- 
quently, contains  the  impurities  added  to  it  in  its  course  through  all  the  other  jars. 

THE    "  BROWN-SEQUARD  "    APPARATUS FIG.  8. 

The  Nos.  I,  2,  5,  6  represent  four  of  the  six  bell  jars  in  the  series. 

a,  represents  the  gas  meter. 

i,  represents  a  small  Erlenmeyer  flask  containing  about  too  c.  c.  of  water.  The  bubbles  pro- 
duced by  the  air  passing  through  the  water  show  whether  aspiration  is  regular  or  not. 

c,  rejiresents  a  Woulff  bottle  attached  between  the  Erlenmeyer  flask  and  pump  to  prevent  the 
entrance  of  water  into  the  apparatus  when  there  is  negative  pressure  in  the  apparatus. 

^,  represents  the  water  tap. 

e,  represents  a  Chapman  water  pump,  which  creates  the  suction  and  maintains  the  ventilation. 

The  glass  and  rubber  tubing  connecting  the  different  parts  of  the  apparatus,  as  shown  in  the 
figure,  has  an  internal  diameter  of  nine  mm.,  while  that  used  to  connect  the  seven-litre  bell  jars 
was  only  five  mm.  in  its  internal  diameter. 

DESCRIPTION    OF    THE    "  liROWN-SEQUARD  "    APPARATUS^FIG.  8. 

The  bell  jars  rest  on  large  ground-glass  plates,  and,  in  order  to  produce  an  air-tight  joint,  the 
base  of  the  bell  jar  is  well  rubbed  with  beef  suet  (well  adapted  for  this  purpose).  In  addition  to 
this,  the  joint  is  sealed  with  melted  paraffine.  If  this  work  is  carefully  done  there  is  no  possibility 
of  leakage  at  these  joints.  The  bell  jars  are  connected  together  by  means  of  glass  tubing  bent  at 
right  angles  and  inserted  through  a  perforated  rubber  cork  fitted  into  the  openings  near  the  top  and 
bottom  of  the  jar.  The  air  enters  the  apparatus  through  the  gas-metre.  The  metre  is  connected 
with  the  first  jar  by  means  of  rubber  tubing  attached  to  the  glass  tube  inserted  into  the  upper 
opening  of  this  jar.  After  passing  through  this  jar  it  takes  its  exit  by  means  of  the  glass  tube 
inserted  into  the  lower  opening,  and  connected  with  a  similar  glass  tube  inserted  into  the  upper 
opening  of  the  second  jar  by  means  of  a  short  piece  of  rubber  tubing.  It  takes  the  same  course 
through  all  the  jars. 

The  bell  jars  shown  in  the  figure  represent  those  used  for  the  rabbits,  and  have  a  capacity  of 
37,000  c.  c.     A  wooden  box,  four  inches  in  depth  and  just  large  enough  to  allow  the  bell  jar  to  be 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  57 

placed  over  it,  was  placed  in  each  of  these  bell  jars.  These  boxes  contained  fine  dry  sawdust  to  a 
depth  of  about  five  cm.,  thus  forming  a  comfortable  bed  for  the  animals,  and  at  the  same  time 
absorbing  the  urine.  In  the  last  experiment  (No.  33)  it  was  found  necessary  to  change  the  saw- 
dust in  these  boxes  every  eight  to  twelve  days.  When  the  sawdust  was  changed  each  week  the 
animals  remained  comfortable. 

The  bell  jars  used  for  the  mice,  sparrows,  and  guinea  pigs  were  exactly  similar  in  construction 
to  those  represented  in  the  figure,  but  only  of  7000  c.  c.  capacity.  For  these  animals  a  false 
bottom  of  wire  netting  was  placed  in  the  bell  jars  instead  of  the  boxes  with  sawdust.  This 
arrangement  served  to  keep  the  mice  and  sparrows  dry  and  comfortable,  but  was  less  satisfactory 
with  the  guinea  pigs. 

For  the  mice  and  sparrows  sufficient  food  and  water  were  placed  in  the  jar  at  the  beginning  to 
last  to  the  close  of  the  experiment.  For  the  guinea-pigs  and  rabbits  this  was  impossible  ;  these 
being  fed  daily  on  cabbage  leaves  introduced  through  one  of  the  openings  in  the  jars.  By  arresting 
the  aspiration  of  air  through  the  apparatus  for  a  few  minutes  there  was  very  little  opportunity  for 
any  change  to  take  place  in  the  confined  air  while  the  animals  were  being  fed. 

In  order  to  facilitate  the  taking  of  samples  of  air  from  the  bell  jars,  a  T-tube  was  inserted 
between  each  of  the  last  three  jars.  The  nunte  gas-burette  was  attached  to  the  stem  of  one  of  these 
T-tubes  and  the  air  aspirated  from  the  jar  by  the  force  of  the  water  flowing  out  of  the  lower  open- 
ing of  the  burette.  By  placing  a  screw  clamp  on  the  rubber  connections  on  either  side  of  the 
T-lube  it  was  possible  to  take  a  sam|)le  of  air  from  the  jar  before  or  after  it,  as  might  be  desired. 
By  stopping  the  aspirating  pump  there  was  rarely  any  difficulty  in  taking  a  sample  of  air  from  any 
of  the  jars  in  the  manner  stated.  On  two  or  three  occasions  a  slight  negative  pressure  in  the  jar, 
caused  by  the  small  amount  of  ventilation  taking  place,  prevented  the  aspiration  of  a  sufficient 
amount  of  air  (100  to  150  c.c.)  to  accomplish  its  analysis  in  the  burette.  Otherwise  no  trouble  was 
experienced  in  the  taking  of  samples  of  air  as  desired.  The  gas-burette  was  connected  with  the 
T-tubes  by  means  of  a  short  piece  of  rubber  tubing  attached  to  the  stem  of  these  tubes  and  ordi- 
narily closed  with  a  sliort  glass  rod.  The  rubber  tubing  was  attached  to  the  three-way  stopcock 
of  the  burette. 

The  results  in  the  ihirty-tliree  experiments  performed  upon  sparrows,  mice,  guinea  i)igs,  and 
rabbits  are  shown  in  the  following  tables. 

In  these  experiments,  as  well  as  in  those  previously  reported,  the  disturbance  of  the  heat-regu- 
lating function  may  have  contributed  to  the  results. 

Absorbers  containing  caustic  soda  or  potash,  or  soda  lime,  were  used  in  experiments  6  to  14 
between  the  third  and  fourth,  and  the  fourth  and  fifth  jars  of  the  series  to  absorb  the  COo  from 
the  air  passing  into  the  last  two  jars.  This  arrangement  failed  to  save  the  lives  of  the  animals 
in  these  two  jars.  In  experiments  15,  18,  and  19,  an  absorption-tube  containing  concentrated 
HjSOj  was  placed  between  the  last  two  jars.  The  results  obtained  in  these  three  experiments 
do  not  differ  from  those  obtained  without  the  H.SO.,  absorbers,  and,  therefore,  give  no  evidence 
whatever  of  the  protective  influence  claimed  for  such  absorbers.  The  jirimary  cause  of  death, 
low  percentage  of  O,  was  still  present  and  active. 

Experiments  20  to  28  were  made  with  the  hope  of  producing  some  slight  tolerance  to  the 
atmospheric  conditions  present  in  these  experiments  on  the  part  of  an  animal  subjected  to  such 
conditions  for  a  considerable  time.  While  there  is  ])ositive  evidence  that  a  mouse  living  under 
these  conditions  for  several  days  can  withstand  an  atmosphere  that  instantly  kills  a  fresh  mouse, 
the  number  of  experiments  made  are  insufficient  to  prove  that  such  tolerance  has  any  great  degree 
of  permanency  ;  yet  the  results  obtained  with  the  mice  carried  through  the  series  of  experiments 
from  20  to  28  indicate  the  probability  that  the  tolerance  obtained  is  maintained  for  at  least  several 
days  afterward,  and  that  such  animal  is  less  likely  to  die  when  again  quickly  placed  into  such  an 
atmosphere  than  one  that  had  not  had  such  an  experience. 

The  guinea-pigs  used  in  experiment  30  seemed  to  be  unable  to  withstand,  with  equal  facility 
with  the  mice  and  sparrows,  the  atmosi)heric  conditions  to  which  they  were  subjected.  Several  of 
them  succumbed  to  oedema  of  the  lungs  during  the  second  week  of  the  experiment,  but  since  this 


58  THE  COMPOSITION  OK  EXl'IKKD  AIR, 

is  the  only  experiment  in  uhicli  these  animals  were  used,  a  positi\c  opinion  on  this  point  cannot 
be  given. 

The  rabbits  in  experiment  31  were  supiiosed,  at  the  lime,  to  have  succumbed  to  the  oppressive 
heat  of  the  laboratory  owing  to  the  season  of  the  year,  but  the  later  experiments  would  indicate 
an  insufficient  amount  of  air  was  aspirated  through  the  bell  jars,  and  it  is  evident  that  leakage  took 
place  through  some  of  the  connections  because  of  the  irregular  order  in  which  death  took  place. 

The  last  experiment  was  made  to  determine  what  the  results  would  be  when  the  proportion  of 
CO2  was  kept  as  low  as  Brown-Sequard  and  d'Arsonval  claim  for  their  experiments.  It  was  found 
impossible  to  aspirate  sufficient  air  per  hour  to  bring  about  this  result.  However,  sufficient  air  was 
aspirated  to  prevent  the  reduction  of  the  O  to  proportions  that  were  insufficient  to  support  life. 
By  this  means  it  was  possible  to  continue  the  exjieriment  for  six  weeks  without  losing  any  of  the 
animals,  or  producing  any  grave  symptoms  in  any  of  tliem. 

In  this  experiment  mercurial  manometers  were  attached  between  the  first  and  second,  and  between 
the  fifth  and  sixth  bell  jars  to  ascertain  the  amount  of  negative  pressure,  if  any,  brought  about  by 
the  conditions  or  by  the  form  and  arrangement  of  the  apparatus.  A  difference  of  about  three  milli- 
metres was  noted  b2tween  the  fifth  and  sixth  bell  jars,  while  no  difference  was  noted  between  the 
first  and  second.  It  was  also  ascertained,  by  placing  a  clamp  on  the  rubber  tubing  connecting  the 
fifth  and  sixtli  jars,  and  continuing  the  aspiration,  that  the  amount  of  negative  pressure  required  to 
break  one  of  the  glass  plates  on  which  the  jars  rested,  as  occurred  in  experiment  32,  was  105  milli- 
metres. From  this  it  may  be  inferred  that  at  times  a  greater  negative  pressure  existed  than  that 
noted  in  the  last  experiment.  Such  extreme  negative  ]jressure  as  was  found  necessary  to  break  a 
glass  plate  45  x  45  x  0.6  centim;tres  could  only  occur  upon  the  entire  arrestation  of  the  air-current 
from  som;  accident  to  the  apparatus.  Under  ordinary  circumstances  we  do  not  believe  that  the 
amount  of  negative  pressure  differed  to  any  extent  from  that  found  in  the  last  experiment. 

The  proportions  of  CO,  and  of  O  present  at  the  time  of  death  bear  a  constant  relation  to 
each  other  in  the  different  experiments.  The  duration  of  life  in  each  instance  was  dependent 
entirely  upon  the  rapidity  of  the  air  current  circulating  through  the  ap|iaratus.  This  statement, 
however,  requires  further  explanation.  If  the  average  rate  of  ventilation  per  hour  for  an  entire 
experiment  is  taken,  it  will  be  found  to  vary  considerably  in  the  different  experiments.  This  is 
evident  when  it  is  stated  that  in  experiment  7  the  rate  had  been  9.8  litres  per  hour  up  to  the  time 
of  the  death  of  the  animal  in  the  third  jar;  in  experiment  8  the  rate  had  been  3.8  litres  per  hour 
at  the  death  of  the  fifth  animal  ;  in  experiment  9  the  rate  had  been  1 1.9  litres  per  hour  at  the  death 
of  No.  5  ;  at  the  death  of  No.  3,  in  experiment  14,  10,2  litres  per  hour  ;  at  the  death  of  Nos.  3,  4, 
and  5,  in  experiment  15,  3.45  litres  per  hour  ;  at  the  death  of  Nos.  3,  4,  and  5,  in  experiment  t6, 
only  1.9  litres  per  hour  ;  at  the  death  of  No.  5,  in  experiment  19,  3.55  litres  per  hour.  From  these 
figures  it  will  be  seen  that  the  average  rate  of  ventilation  per  hour  for  an  experiment  is  not  the 
most  important  factor.  By  referring  to  the  tables  giving  the  details  for  each  of  the  33  experiments 
it  will  be  noted  that  the  rate  of  ventilation  was  frequently  changed.  It  was  usually  increased  con- 
siderably in  the  evening  and  again  decreased  the  next  morning  Frequent  changes  in  the  rate  during 
the  day  were  also  necessary,  because  it  is  practically  impossible  to  get  a  perfectly  steady  current 
with  the  water  pump.  In  carefully  regulating  the  rale  of  ventilation,  the  lives  of  the  animals  were 
controlled  at  will,  and  it  is  upon  the  rapidity  of  the  air-current  toward  the  close  of  the  experiment 
that  the  duration  of  life  depended  in  each  case. 

The  rabbits  used  in  the  last  "  Brown-Sequard  "  experiment  were  weighed  at  the  end  of  the 
experiment  and  their  weight  then  as  compared  with  their  weight  at  the  beginning  of  the  experi- 
ment was  as  follows  : 

No.  I,    before    820  g.,   after  1052  g.,  gain   232  g. 


2. 

900  g-> 

i°55  g-> 

155  g- 

3,  "    917  g.-   ' 

4,  "    1 1 25  g-,  ' 

■'   1190  g., 
''      1047  g-, 

"    273  g. 

loss   78  g. 

5,  ' 

6.  ' 

1220  g., 
'   1665  g., 

"     1352  g; 
"    1544  g-, 

gain  132  g. 
loss  121  g. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE.  59 

At  the  death  of  No.  4,  six  days  after  the  close  of  the  experiment,  tlie  loss  in  its  weight  was 
found  to  have  been  caused  by  the  presence  of  psorosperms  in  its  liver.  This  organ  was  literally 
filled  with  masses  of  these  bodies.  The  loss  of  weight  in  No.  6,  in  the  absence  of  any  other 
observable  causes,  may  be  safely  attributed  to  its  position  in  the  .series  of  bell  jars,  and,  therefore, 
to  the  impurity  of  the  atmosphere  which  it  breathed.  The  estimations  of  the  proportions  of  COj 
and  of  ()  present  in  this  bell  jar,  as  found  from  day  to  day,  denote  atinospheric  conditions  that 
were  undoubtedly  unfavorable  to  the  full  performance  of  its  bodily  functions.  It  ate  less  rave- 
nously than  the  other  animals  and  was  frequently  in  a  stupid,  drowsy  condition. 

At  lhe<:lose  of  this  experiment  an  examination  of  the  blood  of  these  rabbits  was  also  made 
and  (he  pro[)ortion  of  corpuscles  per  cubic  millimetre  determined  with  the  Thoma-Zeiss  hajmo- 
cytonieler,  with  the  following  results  : 

No.  I,  5,170,000  red,  and  24,000  white  per  cubic  mm. 

"  2.  S.337,000  "  "  2i,oco  "        "         "         " 

"  3,  4,510,000  "  "  18,000 

"  4,  4,150,000  "  "  10,000  "        ' 

"  5,  4,950.000  "  "  15,000  "        " 

"  6,  4,375,000  "  "  16,000  "        " 

Here  again  there  is  evidence  that  the  conditions  existing  in  these  bell  jars  were  injurious  to 
some  extent  ;  most  so  in  the  last  jars.  No.  4  ])resents  evidence  of  an  influence  more  serious  in  its 
nature  than  that  presented  by  the  other  animals,  and  this  has  since  been  found  to  have  originated 
from  causes  within  its  own  body. 

Microcytes  were  noted  in  the  blood  of  these  animals.  These  imujature  corpuscles  setmed  to 
be  more  numerous  in  Nos.  4,  2,  and  i  ;  the  blood  of  the  other  animals  presenting  only  a  few  of 
these  bodies. 

Thirty-eight  days  after  the  termination  of  the  experiment  a  second  examination  was  made  of 
the  blood  of  the  five  remaining  animals,  with  the  following  results  : 

No.  I,  4,4co,ooo  red,  and  20,000  white  ])er  cubic  niin. 
"    2,  4,500,000    "       "      15,000      "        " 
"    3,  5,160,000    "       "     30,000      "        " 
"    5,  4,960,000    "       "     30,coo      " 

"      6,    5,890,000      "  "       2O,G0O        "  " 

The  first  and  second  animals  show  a  slight  reduction  and  the  third  and  sixth  an  increase  in  the 
number  of  corpuscles.     No  microcytes  or  blood-plates  were  noticed  this  time. 

The  weight  of  these  animals  at  the  time  of  this  second  examination  of  the  blood  was  as  follows  : 

No.  I,  1040  g.,       lost  12  g.,  since  close  of  experiment. 

"    2,  ,045  g.,         "     10  g., 

"  3,  1265  g.,  gained  75  g.,  "  "  " 
"  5,  1405  g.,  "  53  g.,  "  "  " 
"    6,  1545  g.,        "        I  g.,     "        "      " 

The  loss  of  weight  in  the  first  and  second  animals  may  be  due  to  the  change  of  food.  The 
gain  in  the  others  is  no  doubt  due  to  the  better  atmospheric  conditions  under  which  they  are  now 
living. 


GO 


THE  COMPOSITION  OF  EXPIRED  AIR, 


Post-mortem  examinations  of  a  number  of  tlie  animals  dying  in  the  "  Brown-Sequard  "  experi- 
ments were  made  with  the  greatest  care.  'J'he  organs  were  preserved  in  alcohol  and  mounted  in 
celioidin  for  the  microscopic  examination.  The  gross  appearances  presented  by  the  animals  showed 
a  constant  similarity  to  the  appearances  noted  in  the  animals  used  in  the  experiments  with  artificial 
gaseous  mixtures.  I'lie  constant  appearances  noted  were  those  of  intense  venous  engorgement  of 
all  the  organs  and  tissues.  The  heart  cavities  contained  firm,  dark  clots  of  blood,  filling  both 
auricles  and  ventricles,  those  on  the  right  side  being  usually  much  larger  than  those  on  the  left. 
No  inflammatory  changes  or  serous  exudates  were  found  in  any  instance. 

Microscopic  examination  of  the  organs  presented  no  constant  feature  aside  from  the  manifesta- 
tions produced  by  the  cause  and  mode  of  death.  Engorgement  of  the  blood  vascular  system  was 
noted  everywhere  with  usually  some  degree  of  infiltration  in  the  lung.  No  degenerative  changes 
were  constantly  present.  Those  found  in  isolated  cases — such  as  a  slight  increase  of  connective- 
tissue  elements  between  the  tubules  of  the  kidneys  and  about  the  glomeruli,  and  small  areas  of 
proliferation  of  connective-tissue  elements  in  the  liver — cannot  be  safely  attributed  to  the  experi- 
ment. This  opinion  is  strengthened  by  the  short  duration  of  the  experiments,  and  it  is  probable 
that  the  changes  were  due  to  ante-e.'cperimental  causes. 

The  mode  of  death  as  observed  in  these  experiments  presented  certain  constant  features  which 
were  undislinguishable  from  those  produced  by  slow  asphyxia  under  other  circumstances.  There 
was  a  period  of  excitement,  followed,  in  the  course  of  time,  by  a  period  of  progressive  depression. 
The  breathing,  at  first  rapid,  generally  became  slower,  with  perceptible  lengthening  of  the  respiratory 
pauses,  accompanied  at  a  later  period  by  marked  expiratory  efforts.  Along  with  these  respiratory 
changes  was  usually  noted  a  progressive  muscular  weakness  gradually  deepening  into  paralysis  of 
the  posterior  members.  The  animal  moves  about  with  evident  difficulty,  and  finally  sinks  down, 
remains  lyiiig  on  the  side  or  back,  without  any  other  movements  than  those  of  respiration.  It  now 
presents  a  comatose  condition  from  which  it  cannot  be  aroused  by  striking  the  sides  of  the  bell  jar. 
Death  usually  ensues  through  the  gradual  lengthening  of  the  respiratory  pauses  passing  into  an 
entire  failure  of  respiration.  In  a  small  proportion  of  the  cases,  life  becomes  extinguished  through 
one  or  two  convulsive  seizures. 


No.  I.     Brown-S^quard  Experiment. 


Commenced  at  5  p.m.,  March  2,  1894.     Sparrows  in  i  litre  flasks.     4  in  series. 


The  +  mark  indicates  the  death  of  the  animal. 


Time. 

No.  I. 

No.  2. 

No.  3. 

No.  4. 

Remarks. 

CO,. 

0. 

CO3. 

0. 

COj. 

0. 

CO,. 

0. 

1  7  ,    hrs. 

«7i     " 
i8|     " 
19I-     " 

+ 

48.5    litres     aspirated  each 

hour  ;  too  rapid. 
Changed   to   2.85   litres  per 

hour. 
No.     3     died.      Symptoms 

of  CO2  poison. 
Experiment  stopped. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 

No.  2.     Brown-SSquard  Experiment. 

Commenced  at  1 1.45  a.m.,  March  3,  1S94.     Sparrows  in  7-litre  hell  jars.     5  in  series. 


61 


Ti 

No.  I. 

21  g. 

.So.   2.     21   g. 

No,  3.    21  g. 

No.  4.    21  g. 

No.  5- 

Rcm.irks. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO. 

0. 

CO.. 

0. 

4j 

hrs. 

+ 

36  8  litres  aspirated.  No.  5 
died. 

,9^ 

It 

+ 

No.  4  died  during  night. 
Others  lively. 

22 

It 

No.  3  still  comfortable. 

27 

It 

+ 

No.  3  died. 

2C,l 

+ 

+ 

Nos.  I  and  2  dead. 

4H 

2.8s 

16.99 

5°i  'S-^S 

! 

6.07 

12.63 

736 

13-40 

Examination  of  air  after 
death  of  each  bird. 

No.  3.     Brown-S^quard  Experiment. 

Commenced  at  12.15  •' ■'^'■>  March  5,  1S94.     Sparrows  in  7-litre  bell  jars.     5   in  series. 


Time. 

No.  I.   22  g. 

No.  2.    ig  g. 

No.  3.  27  g. 

No.  4.  26  g. 

No.  5.   25  g. 

Remarks. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

20J  hrs. 
"I      " 

29i       " 

'9l     " 

+ 

+ 

+ 

Current  11.6  litres  per  hour. 
Current    reduced  ;     now  6 

litres  per  hour. 
No.  5  died. 
Nos.  3  and  4  dead. 
Experiment  stopped. 

No.  4.     Brown-Sequard  Experiment. 
Commenced  at  9.30  a.m.,  March  7,  1894.     Sparrows  in  7-litre  bell  jars.     5  in  series. 


Time. 

No.  I. 

21  g. 

No.  2. 

22  g. 

No.  3. 

23  g. 

No.  4. 

25  g- 

No.  5. 

21  g. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

i3i  hrs. 

+ 

14.30 

4- 
4-485 

14.01 

+ 
3-635 

+ 

. 

+ 

Remarks. 


All  the  birds  are  dead.  No 
record  of  amount  of  air 
aspirated. 

Examination  of  air  after 
death. 


62 


THE  COMPOSITION  OF  EXPIRED  AIR, 


No.  5.     Bro\vn-Si';quard  Expkrimknt. 
Commenced  at  6  p.m.,  March  8,  1S94.     Sparrows  in  7-lilrt'  bell  jars.       5  in  series. 


Time. 

No.  I 

21   g. 

No.  2. 

21  g. 

No,  3 

26  g. 

No.  4. 

22  g. 

No.  5. 

25  g- 

CO,. 

0. 

CO,. 

0. 

COo. 

0. 

CO,. 

0. 

CO,. 

0. 

14J    hrs. 

+ 

+ 

+ 

+ 

i8|-     " 

24        " 

+ 

10.83 

6-93 

'3-545 

3-755 

'3-25 

4-35 

13-78  3-465 

14-195 

3-965 

Remarks. 


Nos.  3,  4,  and  5  dead. 
No.  2  died. 

No.  I  died  during  night. 
Examination    of   air  after 
death. 


No.  6.     Brown-Skqu-ard  Experiment. 
Commenced  at  8.45  a.m.,  March  12,  1S94.     Sparrows  in  7-litre  bell  jars.     5  in  series. 


Time. 

No.  I 

23  g. 

No.  2 

23  g- 

No.  3 

23  g. 

No.  4.   23  g. 

No.  5 

27  g- 

Remarks. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 
•3-77 

0. 

4.C6 

CO,. 
8.02 

0. 

8      hrs. 
8|      " 

3-97 

CO.j  absorber?.     Absorbers 

changed,  saturated. 
Nos.  3,  4,  and  5  are  greatly 

oppressed. 
All  are  alive. 
Experiment  terminated. 

No.  7.     Brown-Sequard  Experiment. 
Commenced  at  9  15  a.m.,  March  13,  1894.     Sparrows  in  7-litre  bell  jars.      5  in  series. 


No.  I 

23  g- 

No.  2 

23  g- 

No.  3 

^3g- 

No.  4 

23  g. 

No.  5 

2-g. 

Time. 

Remarks. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

56.6  litres  aspirated. 

5f  hrs. 

I. II 

19.22 

1-49 

17.42 

Absorbers  acting. 

7i     " 

+ 

No.  3  died.     Nos.    i   and  2 
much  oppressed.    Experi- 

ment continued. 

81     " 

2.02 

19.20 

4-77 

14-23 

84.9  litres  aspirated. 
Nos.  I  and  2  died. 

8f     " 

+ 

+ 

Nos.  4  and  5  still  unaffected. 

Experiment  continued. 
169.8  litres  aspirated. 
Nos.  4  and  5  well. 

22       " 

Experiment  terminated. 

26       " 

Nos.  4  and  5  well. 

26|-       " 

12.39 

4-155 

3.08 

17.29 

2.6l 

77.78 

Examination     of  air    after 
death. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 
No.    8.      BROWN-SltQUARD    EXPERIMENT. 

Commenced  at  3.45  p.m.,  March  14,  1894.     Sparrows  in  7-litre  bell  jars.     5  in  series. 


63 


Ti 

No.  I. 

29  g. 

No.  2. 

23  8- 

No.  3. 

27  g. 

No.  4. 

26  g. 

No.  5 

27  g. 

Remarks. 

CO». 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

106  litres  aspirated. 

18 

hrs. 

Birds  all  well. 

>9l 

4.28 

7-73 

4.52 

7.12 

N'os.  3  and  4  showing  signs 

20i 

30 

<( 

4.82 

5-ot 

3-27 

3-95 

of  oppression. 
No.  5  most  affected. 
No.  5  died.      121.75  litres 

3>1: 

tt 

+ 

aspirated.  No. 4quitesick. 
Nos.  3  and  4  died  in  night. 

47] 

t( 

856 

+ 
9.665* 

0.96 

+ 
10.06* 

2.875 

3.56 

141. 5  litres  aspirated  and 
experiment  stojjped. 
Examination    of    air  after 
death. 

No.  9.     Hrovvn-Skquard  Experiment. 
Commenced  at  1 1.30  a.m.,  March  16,  1S94.     Sparrows  in  7-litre  bell  jars.     5  in  series. 


No.  I 

29  g. 

No.  2.  23  g. 

No.  3. 

26  g. 

No.  4.     24  g. 

No.  5.    24  g. 

Time. 

Remarks. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

4i  hrs. 

.001036 

'3-37 

.001047 

12.67 

COo    absorbers.         39.6 
litres  aspirated. 

H    " 

Current  increased. 

22     " 

290   litres   aspirated,   or 
13  litres  per  hour.     All 

22J  " 

1.29 

16.41 

2.01 

14.92 

are  well. 
357.9  litres  aspirated.  All 
birds  well. 

30     " 
46J   " 

18.01 

+ 
1.51 

16.68 

+ 
0.468 

13.065 

+ 
2.545 

All  died  during  night 
(aspiration  practically 
nil). 

Examination  of  air  after 
death. 

*  These  .lir  analyses  were  m.i<le  several  hours  after  death,  and  considerable  alteration  mvist  have  occurred  through 
ventilation  in  the  intcnal. 


64 


THE  COMrOSlTlON  OF  EXPIRED  AIR, 


No.  lo.     Brown-Sequard  Experiment. 
Commenced  at  9.15  a.m.,  March  20,  1S94.     Sparro-.vs  in  7-litre  bell  jars.     5  in  series. 


No.  I.   28  g. 

No.  2.  23  g. 

No.  3.   27  g. 

No.  4.  27  g. 

No.  5.   24  g. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

3    hrs. 

COo    absorbers:     all     are 

3f    " 

3.08 

12.24' 

6.73 

12.1 1 

slightly  oppressed. 

5l     " 

4.27 

7-34 

2.61 

9.04 

6i     " 

5-22 

6.89 

2.86 

7-50 

7J    '• 

5-69 

5-69 

4-79 

5-74 

s      " 

Current  increased   for  the 

night. 
25.5  litres  aspirated.  All  are 

somewhat  oppressed. 

23  " 

1. 114 

16.49 

°-5°3 

15-79 

All  are  lively.     360.8  litres 
aspirated,  current  reduced. 

24}  " 

323 

12.46 

1. 20 

14.02 

Becoming  oppressed. 

^s     " 

5.60 

9-74 

3.60 

9.88 

26;-       " 

8.28 

8.6=; 

5-27 

9.14 

27.          " 

, 

7.82 

5-65 

5-1 1 

7.71 

28j-       " 

9.08 

3-13 

6.20 

6.84 

All    are    very     much    op- 

29T    " 

9-51 

+ 

6.34 

5-59 

pressed. 

3°i     " 

9.42 

4.07 

6.42 

4.86 

No.  4  died. 

31       " 

+ 

+ 

+ 

Nos.  3  and  5  died. 
No.  2  died.   No.  i  released. 
Revived  ;  exp.  stopped. 

34    " 

1514 

3-145 

1434 

4-775 

10.965 

3-50 

10-54 

3-77 

Examination    of    air   after 
death. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


65 


No.    II.     Brown-Si'qu.ard  Experiment. 


Commenced  at  11.45  A  .M.,  March  22,  1S94.     Sparrows  in  7-litre  bell  jars.     5  in  series. 


No.  I.  28  g. 

No.  2.  20  g. 

No.  3.  20  g. 

No.  4.  25  g. 

No.  5.  26  g. 

Time. 

Remarks. 

CO,. 

p. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

3ilirs. 

1.41 

14.20 

0.96 

12.98 

COj    condensers. 

+ 

No.  3  died.    Replaced  by 

3i 

4.86 

13965 

a  fresh  bird,  weight  29  g. 
Experiment  continued. 

5l- 

1 

2.06 

11.06 

1.28 

11.30 

34  litres  aspirated. 
Current  increased. 

20J 

152.8  litres  aspirated. 

21 

1.40- 

12.92 

1.99 

12.76 

8|  litres  per  hour  during 
night. 

22 

1.83 
2.16 

12.02 
II. II 

5-19 
6-39 

9.07 
7.90 

Current  reduced. 

All  somewhat  oppressed. 

23 

2.48 

9-45 

7-3° 

6.23 

24 

+ 

No.  4  quite  sick. 

25 

2.79 

9-34 

7-7° 

565 

No.  4  died.     Nos.  3  and  5 

show  great  oppression. 

26 

6.93 

4.86 

27 

6.465 

4.29 
+ 

No.  s  died. 

28 

6.76 

3-53 

28i- 

+ 

No.  3  died.     No.  2  much 

oppressed. 

8.5  litres  aspirated  last   9 

hrs.   E.xp.  stopped.   Nos. 

I  and  2  died  during  night. 

29J 

tt 

14525 

4.29 

^5°9 

4-3° 

3-49 

9545 

8.31 

3-395 

Examination  of   air  after 

1 

1 

death. 

66 


THE  COMPOSITION  OF  EXl'lUKl)  A  IK, 


No.    12.     Brown-Sequard  Experiment. 


Commenced  at  3.45   p.m.,  March   24,1894,     Sparrows  in  y-litre  bell  jars.     5  in  series. 


Time, 


hrs. 


>9 


4oi 

H 

42f 

4,Sf 

444 

46i 

47l 

li 

5" 

65I 

a 

No,  I,    24  y.     No,  2,    25  g. 


COj.  I     O, 


CO3,       O 


No.  3,    26  g. 


CO,.       O 


14-77 


+ 


3412 


No.  4.    27  g.     No.  5.    25  g. 


COs,      o. 


5,018 

3-457 


4-293 


5-947 
5-8S7 

+ 


CO. 


2.264 
1-577 


•36'3-729 


6,436 
4.08 

+ 


3-449 


Remarks, 


31  litres  aspiraied  Current 
slightly  increased, 

334,5  litres  aspirated. 

All  lively,  Ba(H0)2  ab- 
sorber renewed. 

469,75  litres  aspirated. 

Nos,  3,  4,  and  5  oppressed, 

4^6,75  litres  aspirated. 

Current  reduced. 

No,  5  died. 

No,  4  died. 

No,  3  died,  448,75  litres  as- 
pirated.   No,  2  oppressed, 

Nos,  I  and  2  oppressed, 
No,  2  most  so. 

Experiment  stopped.  Both 
revived,  543,5  litres  aspi- 
rated. 

Examination  of  air  after 
death. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 


a7 


No.    13.     Brown-Si£QUArd  Expkriment. 
Commenced  at  12.45  ''-^'i  ^'^ird'  -7,  i894-     Sparrows  in  7-litre  bell  jars.     5  in  series. 


No.  I.  24  g. 

No.  2.  25  g. 

No.  3.   26  g. 

No.  4.  25  g. 

No.  5.  25  g. 

Time 

Reni.arUs. 

CO,.'    0. 

CO.. 

0. 

CO.. 

0. 

CO,. 

0. 

CO.. 

0. 

I  hrs. 

8  litres    aspirated.     Cur- 

■ 

rent  reduced. 

2i      " 

35  litres  aspirated. 

31    " 

1. 12 

14,565 

0.676 

13.636 

5      " 

53  litres  aspirated.    Cur- 

rent increased  for  night. 

20I    " 

4.00 

11.279 

2.827 

'0-556 

249  litres  aspirated. 

."Ml  lively. 

^'^ :: 

4.00 

8.279 

329 

7-055 

Nos.  3,  4,  and  5  becoming 

23! " 

^ 

oppressed. 

25      " 

4.644 

6.145 

3.76 

4-524 

Al!  are  much  oppressed. 

26|  '; 

1 

1-655 

7-685 

1054 

5.80    Current  slightly  increa.scd. 

281      " 

;  307  litres  aspirated.     Cur- 

rent  increased  for  night. 

282     " 

523  litres  aspirated.  All 
are  well. 

44l    " 

4-477 

11.94 

2.468 

11.974 

566  litres  aspirated.  Leak- 

46I   " 

age,  meter  clianged  to 
other  end  of  bell  jars. 

47       " 

5-365 

9-365 

3-518 

8.60 

.Ml  showing  signs  of  op- 
pression. 

47J    " 

4.609 

8-45 

3041 

7-794 

48J    " 

4-113    7498 

4-03 

5-95  1 

49J    " 

4.938    5-508 

4-25 

4-54 

5oi    " 

4-932    4-545 

6,327 

3-894 

5>l    " 

-f- 

No.  5  died. 

S3      " 

+ 

+ 

Nos.  3  and  4  died. 

54J    " 

+ 

No.  2  died.  No.  i  released. 

S4J    " 

Experiment  stopped. 

14.746 

2.186   13.92 

3-912 

6-4875 

34395 

Examination  of  air  after 
death. 

68 


THE  COMPOSITION  OF  EXPIRED  AIR, 


No.  14.     Brown-Sequard  Experiment. 


Commenced  at  12  m.,  March  30,  1894.     Mice  in  7-litre  bell  jars.     5  in  series. 


Time. 


No.  I.   ig.sg. 


5 1   hrs. 


21 

22i 

24 

26f 

t( 

28i 

" 

29 

3° 

46 

(( 

694 

(( 

71 
74 

(4 

73i 
76 

CO..       O. 


No.  2.    20  g. 


COj.       O 


No.  3.   27  g. 


CO,.       O. 


12.40 


No.  4.   19  g. 


+ 


353 


COj. 


.278 
1.799 

3-67 
3-25 

2-975 
2-495 


O. 


No.  5.   27  g. 


CO2.        O. 


13.699 

14.58 

1 1. II 

10.143 

9-213 
8.06 


5-476 


+ 
3277 


■645 
2-034 

3-357 
3.068 

2.777 
2.013 


14.76 
13.66 

10.268 

9i° 


5-656 


+ 


Remarks. 


7.176 


4-53 


26  litres  aspirated.  Cur- 
rent increased.  Nos.  3, 
4,  and  5  slightly  op- 
pressed. 

157  litres  aspirated. 

No.  3  is  slightly  op- 
pressed. 

i6i-J-  litres  aspirated. 

Nos.  3,  4,  and  5  slightly 
oppressed. 


166  litres  aspirated.  Cur- 
rent increased.  All 
more  or  less  oppressed. 

393  litres  aspirated.  All 
still  oppressed.  Current 
reduced. 

413  litres  aspirated.  No. 
5  died  in  night.  Others 
very  sick. 

No.  3  died. 

414  litres  aspirated. 
No.  4  died. 

4155  litres  aspirated. 
Aspiration  stopped.    417 

litres  aspirated. 
Examination  of  air  after 

death. 


AND  ITS  EFFECTS  UPON  ANIMAT,  I.II-K. 

No.  15.     Brown-Sequard  Experiment. 
Commenced  12  .\i.,  .April  2,  1894.     Mice  in  7-litre  bell  jars.     5  in  series. 


09 


No.  I.  19.5  g. 

No.  2.    17  g. 

No.  3.     18  g. 

No.  4.   17  g- 

No.  5.    17  g. 

Remarks. 

Time. 

CO.. 

0. 

CO.. 

0. 

CO.. 

0. 

CO,. 

0. 

CO.. 

0. 

IS 

irs. 

3839 

'5-356 

8.671 

8.671 

2  litres  aspirated. 

•si 

ti 

7.865 

9-55 

6-39 

5-534 

5-75 

Leakage. 

17 

it 

7-41 

S-357 

9.93 

18 

ti 

7.69 

5-38 

6.45 

9.248 

5.0  litres  aspirated. 

"9i 

(1 

5.5  litres  aspiratctl. 

'9i 

(t 

17  litres  aspirated. 

22 

(i 

19.5  litres  aspirated. 
Current  increased. 

23 

(( 

109  litres  aspirated. 

39 

(( 

1-765 

13-84 

1.78 

'439 

40* 

11 

2.40 

13.16 

2-39 

12.517 

4.* 

(( 

372 

12.51 

3.717   ir.639 

42i 

It 

3-867 

11.22 

5.048  10.00 

44 

4( 

5-05 

9-53 

5-57       8.406 

4SJ 

l( 

5-17 

9-79 

378 

142.5  litres  aspirated. 

46J 

11 

.... 

142.5  litres  aspirated. 

47J 

If 

62^ 

11 

6.845 

8.60 

1.98 

6.06 

All       somewhat       op- 

63i 

ti 

7-49 

7.67 

2-35 

4.70 

pressed.   183  litres  as- 
pirated. 

64* 

tl 

7.29 

7.29 

3-03 

3.98 

185  litres  aspirated. 

6SJ 

tt 

7.40 

6-37 

3-59 

396 

All     considerably     o])- 

66 

H 

7-75 

5.86 

2.92 

3-86 

pressed. 

67 

it 

7-319 

6.178 

3.26 

3.58 

68 

it 

7.27 

6.04 

3-43 

3-33 

69 

It 

8.22 

S-io 

3.63 

2-IS 

70- 

tt 

8.25 

4-78 

4.00 

2.96 

71 

ti 

7.61 

S-39 

3-44 

3-25 

71I 

It 

Current     increased  ; 
189.5  ''""es  aspirated. 
A//  much  oppiesscd. 

86} 

It 

3.60 

12.93 

2-35 

1365 

All    quite    lively  ;    367 
litres  aspirated. 

1 

All  absorbers  renewed. 

87i 

11 

5248 

12.58 

3-19 

12.77 

SBi 

(1 

5456 

12.32 

4.14 

12.15 

89i 

u 

7-47 

10-34 

5.465    10.546 

All     absorbers     acting 

poorly. 

90  ■ 

It 

7.66 

9-875 

6.22 

9.707 

92; 

«( 

8.37 

9-335 

6.346 

9.519 

93 

tt 

9.17 

8.508 

7.66 

1    8.141 

94 

tt 

9.67 

7-375 

8.365 

7-307 

1               •                  -1 

9Si 

tt 

9-93 

7-35 

8.318 

7.68 

373     litres     aspirated. 
Current     slightly    in- 
creased. 

96 

It 

+ 

+ 

+ 

+ 

Nos.  2,  3,  4,  and  5  dead  ; 
382  litres  aspirated. 

Experiment  slopped. 

lioi 

it 

•0-939 

6.5^ 

12.60     4.55 

12.28 

3-93 

12.31 

4.86 

Examination  of  air  after 
death  of  mice. 

70 


THE  COMPOSITION  OF  KXPIRED  AIR 


No.   i6.     Brown-Sequard  Experiment. 


Commenced  at  lo  a.m.,  April  9,  1S94.     Mice  in  7-litre  bell  jars.     5  in  series. 


No.  I 

7g. 

No.  2 

15  g. 

No.  3. 

18  g. 

No.  4.    25  g. 

No.  5 

19  g- 

Remarks. 

CO2. 

0. 

COj. 

0. 

CO2. 

0. 

COj. 

0. 

CO,. 

0. 

7i  hrs. 

7.5     litres    aspirated.       All 

oppressed.      Current     in- 

creased. 

Si. 5  litres  aspirated. 

22|    '• 

Current  reduced. 

86  litres  aspirated.  All  ex- 
cept No.  I  oppressed 
Current  increased. 

3'i    " 

+ 

+ 

+ 

90.5  litres   aspirated.-     Nos. 

47       " 

3,  4,  and  5  died  in  night. 
The  experiment  stopped. 

16.317 

3.80 

13-3° 

4.02 

12.05 

5-437 

Examination  of  air  after 
death. 

AND  ITS  EFFECTS  UPON  ANIMAL  LIKE. 


71 


Time. 


5}hrs. 


-^>i 

' 

30 

tt 

44J 

tl 

51* 

5-4 

it 

53 

68 


68* 

it 

69A 

v'i 

72A 

it 
ii 
if 

75 
76 

u 

77 

79i 

tt 

io4i 

it 

117* 
ii8i 

it 

121+ 

122. 

u 

123; 
124: 
12  1 

tt 
tt 
tt 

I22I 

■' 

125 

'25 

I2S 

>25i 

(< 

No.  17.     Brown-S^qu.ard  Experiment. 
Commenced  at  12  m.,  April  11,  1S94.     Mice  in  7-litre  bell  jars.     5  in  series. 


N'o.  I.  7  g.   I  No.  2.  15  g.  ,  No.  3.  16  g. 


CO..  ,     O.    I  CO,.  I    O.     I  CO, 


O. 


Nq.  4.   23  g. 


CO, 


O. 


No.  5.    171;. 
CO,.       o. 


(3. 48     8.80 
12.129  7.067 


11.346 

12.09 
12.007 

13.66 

1513 

15.08 


7.88 

7.38 

7.49 

6.256 

4.59 
4.13 


»5-6i3  i-^3 


10.919 

10.919 

11.06S 

II. II 

12.63 

12.65 


7.00 
7.08 
6.297 

5-465 
4.689 
4.506 


12.989;  4.29 


a.  Fresh  house  mouse  placed  in  No.  5  jar. 

b.  "     white        "         "  "       5    " 

<=•         5    " 

<!•         4   " 

e-         '       3    " 


12. 1  iS 

8-325 

12.645 

7.41 

) 

12.78 

6.92 

12.75 

6.519 

13.35 

5-76 

14.285 

6.405 

15.13 

436 

15.26 

3-86 

15.91 

347 

11. II 

6.536 

11-73 

7.00 

11.74 

5-68 

12-535 

5.22 

12-737 

4-94 

13.08 

4-17 

13.96 

3-77 

a 

b 

c 

Remarks. 


9.5  litres  aspirated.  All 
slightly  oppressed.  Cur- 
rent increased. 

47  litres  aspirated.  Cur- 
rent reduced  some- 
what. 

53.5  litres  aspirated. 
All  oppressed  ;  current 
again  increased. 

122.5  litres  aspirated  ;  all 
lively  again. 


131.5  litres  aspirated. 
All  more  or  less  op- 
pressed. Current  in- 
creased. 

179  litres  aspirated.  All 
lively  again.  Current 
considerably  reduced. 


186.5  litres  aspirated. 
Current  increased.  .-Ml 
oppressed. 

293.5  litres  aspirated.  All 
are  lively  again. 

Current  somewhat  re- 
duced for  the  next  24 
hours. 


360.5  litres  aspirated. 
All  show  consider- 
able depression. 


Mice    are     much     op- 
pressed.      The     ex- 
periment     is      now 
stopped.  All  revived. 
^364.5  litres  aspirated. 


Died  in  two  minutes. 
Lived  to  end  of  experiment. 
Died  in  half  a  minute. 
Died  in  half  an  hour. 
Died  in  six  minutes. 


72 


THE  c;oMro.srnoN  of  expired  aik. 


No.   iS.     Brown-Skquard  Experiment. 


Commenced  at  9.45  a.m.,  April  17,  1894.     Mice  in  7-litre  bell  jars.     5  in  series. 


Time. 


7ihrs. 


22f    " 


5'f  " 


49 


49i 

« 

■soi 

*' 

s^^ 

■S.S  ■ 

*' 

.S,i 

S3i 

■i4 

54 

.S6i 

(t 

65i 

No.  I,  14  g. 


COj.       o 


No.  2,  23  g. 


CO,.       o 


No.  3,  23  g. 


CO..       o 


No.  4,  25  g. 


COj. 


I'  -34 
12.21 

13-15 


12.94 


No.  5,  31  g. 


CO..  O 


8-93 
7-25 
6.278 


d 

e 

f 

6-945 


Remarks. 


12.897 

13-77 
14.479 


13-945 


7.12 

5-66 
4-944 

a 

b 


5-46 


8  litres  aspirated.   .All  are 

slightly    oppressed. 

Current  increased. 
133  litres  aspirated.     All 

are  lively. 
159.5     litres     aspirated. 

Current  continued. 
219  litres.     All  are  more 
or  less  oppressed 


Experiment  stopped.  All 
living  ;  also  white 
mouse  placed  in  No.  5, 
and  small  gray  mouse 
in  No.  4,  as  well  as 
mouse  d. 


a  Fresh  house  mouse  in  No.  5  ;  died  in  one  minute. 

b  No.  5  of  Experiment  16  in  No.  5  ;  died  in  one  minute. 

c  White  mouse,  used  in  Experiment  16,  in  No.  5  ;  remained  alive  to  end  of  experiment. 

d  White  mouse,  used  before,  in  No.  4  ;  remained  alive  to  end  of  experiment. 

e  House  mouse  (fresh)  in  No.  4  ;  remained  ahve  to  end  of  experiment. 

f  House  mouse  (large)  in  No.  4  ;  died  in  two  minutes. 


AND  ITS  EFFECTS  UPON  ANDFAI.  I.Il-E. 


73 


No.  19.     Brown-S^quard  Experiment. 


Commenced  at  10.30  .\..m.,  .April  20,  1894.     Mice  in  7-litre  bell  jars.     5  in  series.     HjSO^  absorber. 


No.  I,  7  g.      No.  2.  7  g.       No.  3.  7g. 


'lime. 

6hrs 
23 


29 
30 


3' 
47*" 


7oi" 

y('i  " 

78J" 
79i" 

94*" 
95i" 


o. 


CO, 


io3i  '■ 

118J" 

118J" 

.i8i'' 

118J" 

118J" 

119  " 

120A" 

I2lA-' 

O.      CO,.      o. 


No.  4,   18  g.  No.  5,  33  g. 


CO,.         O.         CO,. 


7.627 
8.568 


9  637 
9.62 


587 
9159 


o. 


II . 716  10.58 
10.029  (0.69 


Remarks. 


13-73 


9-73 
9'S 


'3- 


18.5  litres  aspirated     .Ml 

show  oppression. 
'33-5  litres  aspirated.  .Ml 
oppressed.  Current  re- 
duced slightly. 
8.226'  Current  the  same. 
y.AiS]  '44  litres  aspirated 
I      are   opjiressed. 
rent  increased. 
213    litres;    current 

same. 
306.5  litres.     All  are  op- 
pressed.    Current    re- 
duced. 


11.238 


,809 
.238 


All 
Cur- 

the 


7.70 
10.87 


4-23 


14. 12 


i: . 267 
7.40 


a 
b 

d 

+ 

3.816 


324  litres  aspirated.  Cur- 
rent increased. 

406  litres  aspirated.  Cur- 
rent reduced. 


421  litresaspirated.  Cur- 
rent the  same. 

428.5  Hires.  Nos.  3,  4, 
and  5  are  very  sick. 


No.  5  died. 

The  others  are  very  sick, 
especially  No.  4. 


No.  4  died, 
stopped, 
revived. 


Experiment 
Others  soon 


a  No.  4  of  last  experiment  placed  in  No.  5  jar  ;  died  in  two  minutes. 

b  White  mouse,  used  in  Experiment  17,  placed  in  No.  5  jar  ;  died  in  two  and  one-half  minutes, 
c  White  mouse,  used  in  Experiment  17,  placed  in  No.  4  jar ;  died  in  three  and  one-half  minutes, 
d  Small  mouse,  used  in  Experiment  17,  placed  in  No.  5  jar  ;  died  in  one  minute. 


74 


THE  COMPOSITION  OF  EXPIRED  AIR, 
Nos.  20-28.     Brown-S^quard  Experiments. 


Commenced  at  2.30  p.m.,  April  25,  1894  ;   encleil  at  June  5,  1894.     Mice  in  y-Iitre  bell  jars. 

5  in  series. 


No.  I,    7  g.      No.  2,   15  g. 

No.  3,   18  g. 

No.  4,  25  g. 

No.  5,   19  g. 

Remarks. 

CO,. 

0. 

COj. 

0. 

CO,. 

0. 

COj. 

0. 

CO,. 

0. 

3  hrs. 
i8i  " 
26i   " 

43i" 
49i  " 

68     " 

75     " 
91I" 

93     " 

+  a 

9  litres  aspirated.  Current  con- 
tinued. 

87.5  litres  aspirated.  All  com- 
fortable. 
94.5     litres     aspirated.      All 
slightly  oppressed.    Current 
increased. 

139.5  litres  aspirated.    All  de- 
pressed.     Current  reduced. 

147  litres  aspirated.     Consid- 
erably depressed.     Current 
increased. 

324.5     litres    aspirated.      All 
lively.     Current  reduced. 

332  litres  aspirated.     Current 
continued. 

355    litres   aspirated.      No.  5 
died  ;     No.    4    greatly    de- 
pressed. 

357  litres  aspirated.     Experi- 
ment stopped  ;  all  soon  re- 
vived. 

Continued  as  Experiment  21,  after  intermission  of  two  days.     May  i,  1S94. 


4ihrs. 

19I" 
2  8i  " 

44     " 

52*  ■' 
68     " 

72     " 


Fresh  mouse  in  No.  5. 

26  litres  aspirated.  All  lively. 
Current  reduced. 

145.5  litres  aspirated.  Current 
the  same. 

i6o  litres  aspirated.  Current 
increased,  showing  depres- 
sion. 

341.5  litres  aspirated.  All 
lively  again.  Current  re- 
duced. 

351.5  litres  aspirated.  De- 
pressed. Current  increased. 

459  litres  aspirated.  All  more 
comfortable.  Current  re- 
duced. 

466.5  litres  aspirated.  Experi- 
ment stopped. 


7  hrs. 

3' 

47 1  " 
55 i  " 
7'     " 


71 

7: 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 
Continued  as  Experiment  22,  after  interval  of  three  days.     May  7,  1S94. 


to 


+  b 


12  litres  aspirated.  All  slightly 
I    oppressed.     Same    current. 

68.5  litres  aspirated.  All  con- 
siderably oppressed.  Same 
current. 

76.5  litres  aspirated.  .All  much 
oppressed.  Current  in- 
creased. 

202.5  litres  aspirated  Current 
reduced  slightly. 

,222  5  litres  aspirated.  Cur- 
rent the  same. 

243  litres  aspirated.  No.  4 
died  in  the  night ;  others  op- 

I    pressed. 

248.5  litres  aspirated.  Experi- 
ment stopped  ;  all  soon  re- 
vived. 


Continued  as  Experiment  23,  after  interval  of  three  days.     May  ii,  i8;4. 


63  hrs. 
2<;3   '• 


46i  " 
48!  '• 
60I  " 
7oi   " 


703  •' 


1 

+ 

+ 
+ 


+ 


I18  litres  aspirated.  Four  mice 
placed  in  No.  4. 

S9.5  litres  aspirated.  Two 
mice  in  No.  4  are  dead;  re- 
moved. 

109.5  litres  aspirated. 

122.  5  litres  aspirated. 

147.5  litres  aspirated. 

148  litres  aspirated.  Two  re- 
maining mice  in  No.  4  died  ; 
also  No.  3. 

Experiment  discontinued  ; 
soon  revived. 


Continued  as  Experiment  24,  after  interval  of  two  days.     May  16,  1894. 


3  'irs 

1 

23h  " 

47*" 

65*" 

7>*" 

74*" 

Fresh  mice  in  Nos.  3  and  4. 
22.5  litres  aspirated.  Cur- 
rent continued. 

121. 5  litres  aspirated.  All 
lively. 

211. 5  litres  aspirated.  All  more 
or  less  oppressed. 

276  litres  aspirated.  All  more 
or  less  oppressed. 

325  litres  aspirated.  All  more 
or  less  oppressed. 

341.5  litres  aspirated.  Consid- 
erably oppressed  ;  experi- 
ment stopped. 


76 


2i^hrs. 
28     " 
45     " 

Soi" 

69I" 

75     " 


THE  COMPOSITION  OF  EXPIRED  AIR, 
Continued  as  Experiment  25,  after  interval  of  two  days.     May  21,  1894. 


103.5  litres  aspirated.  All  much 
oppressed  ;  same  current. 

130  litres  aspirated.  All  much 
oppressed  ;  same  current. 

198.5  litres  aspirated.  All 
much  oppressed  ;  same  cur- 
rent. 

266.5  litres  aspirated.  All 
much  oppressed  ;  same  cur- 
rent. 

323.5  litres  aspirated.  All 
much  oppressed  ;  same  cur- 
rent. 

340  litres  aspirated.  Experi- 
ment stopped  ;  all  soon  re- 
vived. 


Continued  as  Experiment  26,  after  interval  of  one  day.     May  25,  1894. 


7|hrs. 

22|    ' 

7'l 
78 


4.5  litres  aspirated.  All  de- 
pressed ;   current  increased. 

147  litres  aspirated.  All  de- 
pressed ;   same  current. 

392.5  litres  aspirated.  Sunday 
between. 

394.5  litres  aspirated.  Experi- 
ment stopped  ;  all  soon  re- 
vived. 


Continued  as  Experiment  27,  after  interval  of  one  day.      May  29,  1S94. 


4  hrs. 

20i   " 

Ml" 

44i" 

68i  " 
75     " 


5  litres  aspirated.  Show  op- 
pression ;  current  increased. 

69  litres  aspirated.  Current 
reduced. 

74  litres  aspirated.  Much  op- 
pressed ;  current  increased. 

77  litres  aspirated.  Current 
again  increased. 

146  litres  aspirated.  More 
lively  ;  current  reduced. 

[52.5  litres  aspirated.  Current 
increased. 

301,5  litres  aspirated.  Current 
reduced. 

317  litres  aspirated.  Experi- 
ment stopped  ;  revived. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 
Continued  as  Experiment  28,  after  interval  of  one  day.     June  2,  1894. 


4ihrs. 

21J  " 

45     " 

5^i  " 
68J  " 

75     " 


7    litres    aspirated.      Current 
increased. 

134.5  litres  aspirated.     Same 
current. 

227.5  litres  aspirated.  Current 
reduced. 

258   litres    aspirated.      Same 

current  continued. 
395  litres  aspirated.     Current 
again  reduced. 

434  litres  aspirated.      Experi- 
ment stopped  :   revivod. 


a  No.  I  of  Experiment  17  placed  in  Nn.  5  ;  died  in  one-half  minute, 
b  No.  3  of  Kxperiment  19  placed  in  No.  4  ;  died  in  three  minutes. 
c  No.  2  of  Experiment  17  placed  in  No.  5  ;  died  in  one  minute. 

No.  29.     Brown-S^quard  Experiment. 
Commenced  at  5.15  p.m.,  June  5,  1894.     Mice  in  7-litre  bell  jars.     5  in  series. 


Time. 


16    hours. 


24 


No.  I.    II  g  I  No.  2.      9  g.    No.  3.     12  I 
CO,.      O.      CO,. 


40  i 

47  i 

64  i 

70 
72A 

87  J 
94i 

96.} 

114 

114 
114 


ii4i 
•■5i 


COj.      o. 


No.  4.     16  g. 


CO.. 


TO.SI 


n.80 


+ 


No.  5.     19  g. 


CO.. 


7-45 


Remarks. 


5.80 


+ 


121  litres  aspirated.  Cur- 
rent reduced  ;  all  are 
lively. 

129  litres.  Current  in- 
creased ;  some  oppres- 
sion. 

301.5  litres.  Current  re- 
duced. 

335.5      litres     aspirated. 

(Current  increased  ;  some 

oppression. 

451  litres.  Current  re- 
duced. 


460  litres.  Current  same  ; 

some  oppression. 
5J5.5     litres.        Current 

much  reduced. 
541    litres.     Current   in- 
creased ;      greatly    op- 
pressed. 
545.5     litres.        Current 

same. 
Nos.  4  and  5  died  in  the 

night. 
No.  I  of  last  experiment 

placed   in   jar    No.    5  ; 

remained  alive. 
No.  2  of  last  experiment 

|)laced    in    jar    No.    4  ; 

alive. 
No.  3  of  last  experiment 

placed    in   jar    No.    3  ; 

alive. 
565.5  litres  aspirated. 
567   litres  aspirated  ;  all 

mice  alive  ;  experiment 

stopped. 


78 


THE  COMPOSITION  OF  EXPIRED  AIR, 


No.  30.     Brown-Skquard  Experiment. 
Commenced  at  1.15  p.m.,  June  13,  1894.     Guinea-pigs  in  7-litre  bell  jars.     5  in  series. 


Time. 


No.  I. 


No.  2. 


\Vt.  172  g.     \Vt.  185  g. 


No.  3. 


No.  4. 


No.  5. 


Wt.  197  g.  i  \Vt.  275  g.    Wt.  287  g 


3    hou 

18+ 


2ii 


44i 
7Sf 

94]: 

"5f 

I22f 

i48i 

i63f 
171T 
187  J 

i94t 

211} 
23Si 


+ 


+ 


+ 

Wt.  555 


Remarks. 


Nos.  4  and  5  are  oppressed.  Cur- 
rent 24  litres  per  hour. 

No.  5  dead.  Great  negative  pres- 
sure. Fresh  air  su|)plied,  and 
No.  5  replaced  by  a  fresh  guinea- 
pig.     Experiment  continued. 

60  litres  i^er  hour  ;  all  are  lively. 

Animals  fed  ;  bell  jars  cleaned. 
Animals  replaced. 

Animals  fed  ;  all  well  and  dry  ; 
60  litres  per  hour. 

Again  fed  ;  all  lively  and  dry  in 
bottom  of  cages. 

30  litres  per  hour;  Nos.  4  and  5 
oppressed  ;  animals  fed. 

80  litres  per  hour  ;  animals  fed. 

80  litres  per  hour  ;  cages  cleaned  ; 
animals  fed. 

40  litres  per  hour  ;  animals  fed  ; 
all  oppressed. 

50  litres  per  hour  ;  animals  fed. 

50  litres  per  hour  ;  animals  fed. 

45  litres  per  hour  ;  animals  fed. 

No.  I  dead  of  oedema  of  lungs  ; 
experiment  continued  with  4 
animals. 

No.  3  died  in  night  of  cedema  of 
lungs.     Experiment  continued. 

Nos.  2,  4,  and  5  living,  but  much 
oppressed.  Experiment  stopped. 


Experiment  lasted  g  days  and  20  hours.     No.  5  died  three  days  after  close  of  experiment.      No  autopsy. 


AND  ITS  EFFECTS  UPON  ANIMAL  LIFE. 

No.  31.     Brown-Sequard  Experimknt. 

Commenced  at  5.15  p.m.,  June  25,  1894.     Rabbils  in  37-litre  bell  jars.     5  in  series. 


79 


Time. 


No.  I. 

1S50  g.  No.  2.  1325  g. 

CO,. 

..        .nj     0. 

No.  3.  1564  g.  No.  A.  140S  g.  No.  5.  1647  n 

I 

COj.      O.      CO,.  I    o. 


CO..      o. 


r6    hours. 

24         " 

4oi       " 

Remarks. 


t)0  litres  per  hour  aspi- 
rated. 

34  litres  per  hour  ;  some 
oppression. 

Nos.  2  and  3  died  in 
the  night.  Experiment 
stopped. 


No.  32.     BROwx-Sitgu.VRi)  Experimknt. 
Commenced  at  10.15  •■^•■'^i.,  December  4,  1894.     Rabbits  in  37-litre  bell  jars.     6  in  series. 


No.  I. 

No.  2. 

No,  3. 

No 

•  -t. 

No 

.  5- 

.No.  6. 

2iS5g. 

1945  g- 

1965  g- 

2025  g. 

2500  g. 

3043  g- 

Time. 

Remarks. 

CO,. 

0. 

CO.. 

0. 

CO.. 

0. 

CO,. 

0. 

CO,.      0. 

CO,. 

0. 



% 

i 

i 

% 

% 

% 

3l  hrs. 

3-9' 

■5-87 

5-33 

14.19 

120  litres  per  hour  as- 

pirated. 

4;    " 

4.13 

'4-47 

5.08 

■317 

St  " 

413 

14.56 

5.02 

13.62 

26;    " 

.S-5.S 

14.67 

6.17 

13-67 

27A  " 

4.18 

«4-25 

6.19 

11.32 

-9:    " 

6.00 

14.19 

7.21 

13-86 

46}  " 

413 

1505 

4.83 

14.00 

5'*:: 

4-38 

'4-74 

5-88 

12.26 

S3     " 

6.10 

13.20 

7.17 

11.90 

54     " 

S-28 

13.90 

6.05 

12.40 

71*  " 

3-47 

iS-4«> 

4-05 

13-83 

74i  " 

5.92  !l2.82 

6.81 

11.46 

78.i  " 

5 -8 1 

13.69 

7-38 

IT.82 

94J  " 

+ 

+ 

+ 

+ 

+ 

All      the      rabbits     are 
smothered   except  No. 
6.       The    glass    plate 
under    No.    6     broke 
during    the   night  and 
arrested  the  aspiration 
of     air     through    the 

other  bell  jars. 

80 


THE  COMI'OSITION  OF  EXPIRED  AIR, 


No.  ;^;^^.     BRowN-SitQUARD  Experiment. 
Commenced  at  2.45  r.M.,  December  8,  1894.      Rabbits  in  37-litre  bell  jars.     6  in  series. 


No.  I. 

No.  2. 

No.  3. 

No.  4. 

No.  5. 

No.  6. 

820  g. 

900  g. 

917  g- 

1125  g- 

1220  g. 

1665  g. 

rime. 

Remaiks. 

Days. 

co=.!  0. 

COj. 

0. 

CO2. 

0. 

CO,. 

0. 

CO,. 

0. 

CO,. 

0. 

% 

% 

% 

% 

% 

i 

% 

% 

I 

80  litres  per  hour  aspirated. 

2 

3-0" 

16.03 

363 

14.62 

3 

3-43 

'5-39 

4.32 

13.86 

70  litres  per  hour  aspirated. 

4 

Larger  glass  tubing  used  to 
connect   the  bell  jars.     100 

litres  per  hour  aspirated. 

5 

1-39 

16.68 

1.61 

15-5' 

6 

1.58 

16.27 

1.72 

14.49 

7 

4-94 

14-43 

4.88 

13.86 

8 

4-31 

15-29 

4.46 

14.98 

9 

4-31 

15-29 

4.46 

14.98 

Cages  cleaned  out  ;  148  litres 
per  hour  aspirated. 

10 

2-51 

16.69 

2.72 

15-69 

1 1 

12 

1.08 

16.38 

I-S9 

16.30 

130  litres  per  hour  aspirated. 

13 

2.37 

16.11 

2-5' 

15-54 

14 

1.69 

16.60 

1-99 

15-43 

15 
16 

1-75 

16.55 

2.23 

15-67 

Cages  cleaned  out. 

17 
18 

4.07 

15.22 

5-24 

13-88 

19 

4.69 

15-15 

5-53 

13-74 

20 

4-9' 

16.01 

6.16 

1546 

21 

451 

15-58 

5-85 

14.00 

22 
23 

7.61 

II. 81 

7-75 

11.63 

Cages  cleaned  out  ;  130  litres 
per  hour  aspirated. 

24 

4.88 

15-03 

6.32 

13-63 

25 

5.58 

14.20 

6.52 

13-35 

120  litres  per  hour  aspirated. 

26 

5-38 

14.18 

6.31 

12.73 

27 

6.84 

14.00 

6.51 

14. II 

125  litres  per  hour  aspirated. 

28 

6.68 

13.26 

6.69 

13.00 

29 

30 

6.26 

13-71 

7-44 

12.53 

31 

4.89 

14.87 

7. II 

12.74 

32 

4-77 

15-38 

7-59 

12.62 

33 

6-39 

13-37 

7.81 

11.77 

no  litres  per  hour  aspirated. 

34 

4-23 

15-76 

7.46 

11.14 

35 

5-74 

14.17 

8.02 

11.69 

Cages  cleaned  out  ;  No.  6  not 

36 
37 

well  ;  due  to  filth. 

6.67 

13-55 

7.70 

12.45 

No.  6  has  fully  recovered. 

38 

4.42 

14.44 

5-44 

13.06 

no  litres  per  hour  aspirated. 

39 

5-29 

13-S' 

6.81 

12.05 

40 

4.86 

14.88 

7-9° 

12.54 

41 
42 

5-74 

14-45 

6-94 

13-19 

Experiment  stopped. 

1052  g- 

i°55  g- 

1 190  g. 

i°47  g- 

1352  g- 

1544  g- 

Weight  of  animal  at  close  of 
experiment. 

INDEX. 


Abbott,  A.  C J4>  31 

Abbott's  modification  of  Hammond  apparatus  46 

Absorption  tubes 57 

Air,  expired,  micro-organisms  in '3i  33 

"         "  organic  matterin.  .4,  5,  8,  II,  14,  34 

"     oxidizable  matter  in 42 

Ammonia   in   condensed  moisture  from   ex- 
pired air 36 

"  in  air 16 

Animals,  individual  susceptibility  of 22 

Apparatus  for  condensing  moisture 35,  38 

Appendix 33 

Asphyxia,  composition  of  air  producing 17 

"         pathology  of 23 

Atmospheres,  artificial 50 

Bacteria  in  hospital  air 40 

Bergey's  ex[)eriments '3>  33 

Bernard,  C 3 

Bert,  Paul 3.  29 

Beu,  J >>,  15.  31 

Bibliography 29 

Black  Hole  of  Calcutta 2 

Blood-counis 59 

Brown-Secjuard  apparatus 56 

"  and  d'Arsonval 5,  7,  13 

"  experiments 60 

Bunte's  gas  burette 44 

Carbonic  acid,  effects  of 2,  4,  1 7,  47 

Conclusions 24 

Condensing  apparatus 38 

Consumption,  causes  of 26 

Dastre  and  Love 6,  30 

Dust  filter 16,  39 

Fasting,  effects  of,  on  expired  air 15 

Friedlander  and  Herter 19,  29,  31 

Gaseous  mixtures 18 

Habit,  effects  of '9>  25 

Haldane  and  Smith 9,  1 1,  30 

Hammond,  W.  A 4,  29 

"  experiments 42 

Hermans,  J.  T.  F 5,29 

Hospital  ward,  air  of 39 


Injections  of  liquid  condensed  from  exhaled 
air 5,  7,  8,  10,  20,  53 

Leblanc's  researches 2 

hehmann  and  Jessen 8,  15,  30 

Lipari  and  Crisafulli 9.  3° 

I.iibbcrt  and  Peters •...12,34 

Margouty,  B.  M.  E 9,  3° 

Merkel,   S 10,  30 

Micro-organisms  in  expired  air 13,  ^^ 

Moisture  of  exhaled  air 5i  '5)  34 

Moulh,  cleansing  of,  effects  of 37 

"       decomposing  organic  matters  in  ... .    15 

Negative  pressure 58 


Odors,  cause  of 

Olmsted,  Dr.  Ing-.'rsoll 

Organic  matter  in  human  breath 4, 

Oxygen,  diminution  of,  effects  of 

Pettenkofer,  M 

Pulmonary  liipiid,  injection  of 


Ransome,  A 4,  15, 

Rauer 12, 

Regnault  and  Reiset 3, 

Renk,  F 15, 

Richardson,  B.  W 3,  19, 

Richardson's  experiment 

Russo-Giliberti  and  .■\lessi 7, 

Sanfelice,  F 12, 

Seegen  and  Nowak 5, 

Smith,  R.  .\ 4, 


Temperature,  effects  of 

Toleration  of  foul  air,  acquired. 


26 
I 

37 
18 

29 
6 

29 
32 
29 
31 
29 
48 
3° 

3' 
29 
29 

25 
'9 


Uffelmann,  J 8,  30 

Valentin,  G 3,  29 

Ventilation,  insufficient,  effects  of 2,  60 

Von  Hofmann-Wellenhof. ...    8 

Warwick,  Dr.  Hill  S i 

Weight  of  animals,  effect  of  breathing  expired 

air  on 58 

Wurtz,  R 7.  3° 


81 


COLUMBIA  UNIVERSITY  LIBRARY 

This  book  is  due  on  the  date  indicated  belov/,  or  at  the 
expiration  of  a  definite  period  after  the  date  of  borrowing, 
as  provided  by  the  rules  of  the  Libi-ary  or  by  special  ar- 
rangement with  the  Librarian  in  charge. 

DATE  BORROWED 

DATE  DUE 

DATE  BORROWED 

DATE  DUE 

C28(239)M100 

QP121  ^^2 


Billings  .       ,      •      „„^ 

The   conposition  of  expired  air  and 
its  effects  upon  animal  li-e 


MAY  10  1940       C.U.BI^3DS^Y 


J 


t-      "': 


